| 1. |
- Nilsson, David, et al.
(författare)
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Bi-stable and dynamic current modulation in electrochemical organic transistors
- 2002
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 14:1, s. 51-54
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Tidskriftsartikel (refereegranskat)abstract
- Novel electrochemical transistors, based on the conductive polymer PEDOT, operating at driving voltages of only a few volts in bulk material, and with little demand on substrate planarity, are described by the authors. The underlying polymer ion pair PEDOT:PSS is conductive in both oxidized and reduced state. Two transistor architectures, a bi-stable and a dynamic transistor (the first electrochemical specimen of its kind) with an on/off ratio of 105 and 200 Hz modulation speed, were realized.
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| 2. |
- Andersson, Peter, et al.
(författare)
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Active Matrix Displays Based on All-Organic Electrochemical Smart Pixels Printed on Paper
- 2002
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Ingår i: Advanced Materials. - Weinheim, Germany : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 14:20, s. 1460-1464
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Tidskriftsartikel (refereegranskat)abstract
- An organic electronic paper display technology (see Figure and also inside front cover) is presented. The electrochromic display cell together with the addressing electrochemical transistor form simple smart pixels that are included in matrix displays, which are achieved on coated cellulose-based paper using printing techniques. The ion-electronic technology presented offers an opportunity to extend existing use of ordinary paper.
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| 3. |
- Fullham, S, et al.
(författare)
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Carbon Nanotube Templated Self-Assembly and Thermal Processing of Gold Nanowires
- 2000
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 12:19, s. 1430-1432
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Gold nanowires have been produced by the self-assembly of gold nanoparticles onto multi-walled carbon nanotubes. The nanotubes were mixed with a suspension of gold nanoparticles, resulting in a decrease in color intensity of the suspension, and indicating binding between the nanotubes and the gold (see Figure). Subsequent heating in air for 2 min gave rise to continuous nanowires up to 10 μm in length (see also cover).
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| 4. |
- Pitois, C., et al.
(författare)
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Functionalized fluorinated hyperbranched polymers for optical waveguide applications
- 2001
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 13:19, s. 1483-1487
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Tidskriftsartikel (refereegranskat)abstract
- Fluorinated dendritic or hyperbranched polymers are demonstrated for the first time to be potentially useful for optical waveguide applications, for example in telecommunications. The required materials properties include the control of the refractive index over a wide range and UV-crosslinking for ease of processing and stable long-term mechanical properties. The authors report the synthesis of suitable functionalized fluorinated hyperbranched polymers and how the above requirements can be met by functionalization at the periphery of the polymers.
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| 5. |
- Jager, Edwin, 1973-, et al.
(författare)
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Perpendicular Actuation with Individually Controlled Polymer Microactuators
- 2001
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 13:1, s. 76-79
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Tidskriftsartikel (refereegranskat)abstract
- Actuator systems based on conducting polymers, such as polypyrole, with which three-dimensional movement can be controlled, are described. The Figure shows a combination of two such microactuators which are used to “kick” a glass bead across the surface of a silicon wafer. The microfabrication methods used to produce the systems are described and the potential uses, for example microrobotic arms, discussed.
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| 6. |
- Aitola, Kerttu, et al.
(författare)
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High Temperature-Stable Perovskite Solar Cell Based on Low-Cost Carbon Nanotube Hole Contact
- 2017
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Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 29:17
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Tidskriftsartikel (refereegranskat)abstract
- Mixed ion perovskite solar cells (PSC) are manufactured with a metal-free hole contact based on press-transferred single-walled carbon nanotube (SWCNT) film infiltrated with 2,2,7,-7-tetrakis(N, N-di-p-methoxyphenylamine)-9,90-spirobifluorene (Spiro-OMeTAD). By means of maximum power point tracking, their stabilities are compared with those of standard PSCs employing spin-coated Spiro-OMeTAD and a thermally evaporated Au back contact, under full 1 sun illumination, at 60 degrees C, and in a N-2 atmosphere. During the 140 h experiment, the solar cells with the Au electrode experience a dramatic, irreversible efficiency loss, rendering them effectively nonoperational, whereas the SWCNT-contacted devices show only a small linear efficiency loss with an extrapolated lifetime of 580 h.
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| 7. |
- Amdursky, Nadav, et al.
(författare)
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Macroscale Biomolecular Electronics and Ionics
- 2019
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 31:3
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Forskningsöversikt (refereegranskat)abstract
- The conduction of ions and electrons over multiple length scales is central to the processes that drive the biological world. The multidisciplinary attempts to elucidate the physics and chemistry of electron, proton, and ion transfer in biological charge transfer have focused primarily on the nano- and microscales. However, recently significant progress has been made on biomolecular materials that can support ion and electron currents over millimeters if not centimeters. Likewise, similar transport phenomena in organic semiconductors and ionics have led to new innovations in a wide variety of applications from energy generation and storage to displays and bioelectronics. Here, the underlying principles of conduction on the macroscale in biomolecular materials are discussed, highlighting recent examples, and particularly the establishment of accurate structure-property relationships to guide rationale material and device design. The technological viability of biomolecular electronics and ionics is also discussed.
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| 8. |
- Andersson, Peter, et al.
(författare)
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Switchable Charge Traps in Polymer Diodes
- 2005
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 17:14, s. 1798-1803
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Tidskriftsartikel (refereegranskat)
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| 9. |
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| 10. |
- Anusuyadevi, Prasaanth Ravi, et al.
(författare)
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Photoresponsive and Polarization-Sensitive Structural Colors from Cellulose/Liquid Crystal Nanophotonic Structures
- 2021
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 33:36, s. 2101519-
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Tidskriftsartikel (refereegranskat)abstract
- Cellulose nanocrystals (CNCs) possess the ability to form helical periodic structures that generate structural colors. Due to the helicity, such self-assembled cellulose structures preferentially reflect left-handed circularly polarized light of certain colors, while they remain transparent to right-handed circularly polarized light. This study shows that combination with a liquid crystal enables modulation of the optical response to obtain light reflection of both handedness but with reversed spectral profiles. As a result, the nanophotonic systems provide vibrant structural colors that are tunable via the incident light polarization. The results are attributed to the liquid crystal aligning on the CNC/glucose film, to form a birefringent layer that twists the incident light polarization before interaction with the chiral cellulose nanocomposite. Using a photoresponsive liquid crystal, this effect can further be turned off by exposure to UV light, which switches the nematic liquid crystal into a nonbirefringent isotropic phase. The study highlights the potential of hybrid cellulose systems to create self-assembled yet advanced photoresponsive and polarization-tunable nanophotonics.
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| 11. |
- Aparicio, Francisco J., et al.
(författare)
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Transparent Nanometric Organic Luminescent Films as UV-Active Components in Photonic Structures
- 2011
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 23:6, s. 761-765
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Tidskriftsartikel (refereegranskat)abstract
- A new kind of visible-blind organic thin-film material, consisting of a polymeric matrix with a high concentration of embedded 3-hydroxyflavone (3HF) dye molecules, that absorbs UV light and emits green light is presented. The thin films can be grown on sensitive substrates, including flexible polymers and paper. Their suitability as photonic active components in photonic devices is demonstrated.
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| 12. |
- Apostolopoulou-Kalkavoura, Varvara, 1988-, et al.
(författare)
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Thermally Insulating Nanocellulose-Based Materials
- 2021
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 33:28
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Forskningsöversikt (refereegranskat)abstract
- Thermally insulating materials based on renewable nanomaterials such as nanocellulose could reduce the energy consumption and the environmental impact of the building sector. Recent reports of superinsulating cellulose nanomaterial (CNM)-based aerogels and foams with significantly better heat transport properties than the commercially dominating materials, such as expanded polystyrene, polyurethane foams, and glass wool, have resulted in a rapidly increasing research activity. Herein, the fundamental basis of thermal conductivity of porous materials is described, and the anisotropic heat transfer properties of CNMs and films with aligned CNMs and the processing and structure of novel CNM-based aerogels and foams with low thermal conductivities are presented and discussed. The extraordinarily low thermal conductivity of anisotropic porous architectures and multicomponent approaches are highlighted and related to the contributions of the Knudsen effect and phonon scattering.
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| 13. |
- Arjmandi-Tash, Hadi, et al.
(författare)
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Zero-Depth Interfacial Nanopore Capillaries
- 2018
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 30:9
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Tidskriftsartikel (refereegranskat)abstract
- High-fidelity analysis of translocating biomolecules through nanopores demands shortening the nanocapillary length to a minimal value. Existing nanopores and capillaries, however, inherit a finite length from the parent membranes. Here, nanocapillaries of zero depth are formed by dissolving two superimposed and crossing metallic nanorods, molded in polymeric slabs. In an electrolyte, the interface shared by the crossing fluidic channels is mathematically of zero thickness and defines the narrowest constriction in the stream of ions through the nanopore device. This novel architecture provides the possibility to design nanopore fluidic channels, particularly with a robust 3D architecture maintaining the ultimate zero thickness geometry independently of the thickness of the fluidic channels. With orders of magnitude reduced biomolecule translocation speed, and lowered electronic and ionic noise compared to nanopores in 2D materials, the findings establish interfacial nanopores as a scalable platform for realizing nanofluidic systems, capable of single-molecule detection.
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| 14. |
- Arseneault, Mathieu, et al.
(författare)
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The Dawn of Thiol-Yne Triazine Triones Thermosets as a New Material Platform Suited for Hard Tissue Repair
- 2018
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 30:52
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Tidskriftsartikel (refereegranskat)abstract
- The identification of a unique set of advanced materials that can bear extraordinary loads for use in bone and tooth repair will inevitably unlock unlimited opportunities for clinical use. Herein, the design of high-performance thermosets is reported based on triazine-trione (TATO) monomers using light-initiated thiol-yne coupling (TYC) chemistry as a polymerization strategy. In comparison to traditional thiol-ene coupling (TEC) systems, TYC chemistry has yielded highly dense networks with unprecedented mechanical properties. The most promising system notes 4.6 GPa in flexural modulus and 160 MPa in flexural strength, an increase of 84% in modulus and 191% in strength when compared to the corresponding TATO system based on TEC chemistry. Remarkably, the mechanical properties exceed those of polylactide (PLA) and challenge poly(ether ether ketone) PEEK and today's methacrylate-based dental resin composites. All the materials display excellent biocompatibility, in vitro, and are successfully: i) molded into medical devices for fracture repair, and ii) used as bone adhesive for fracture fixation and as tooth fillers with the outstanding bond strength that outperform methacrylate systems used today in dental restoration application. Collectively, a new era of advanced TYC materials is unfolded that can fulfill the preconditions as bone fixating implants and for tooth restorations.
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| 15. |
- Atxabal, Ainhoa, et al.
(författare)
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Energy Level Alignment at Metal/Solution-Processed Organic Semiconductor Interfaces
- 2017
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 29:19
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Tidskriftsartikel (refereegranskat)abstract
- Energy barriers between the metal Fermi energy and the molecular levels of organic semiconductor devoted to charge transport play a fundamental role in the performance of organic electronic devices. Typically, techniques such as electron photoemission spectroscopy, Kelvin probe measurements, and in-device hot-electron spectroscopy have been applied to study these interfacial energy barriers. However, so far there has not been any direct method available for the determination of energy barriers at metal interfaces with n-type polymeric semiconductors. This study measures and compares metal/solution-processed electron-transporting polymer interface energy barriers by in-device hot-electron spectroscopy and ultraviolet photoemission spectroscopy. It not only demonstrates in-device hot-electron spectroscopy as a direct and reliable technique for these studies but also brings it closer to technological applications by working ex situ under ambient conditions. Moreover, this study determines that the contamination layer coming from air exposure does not play any significant role on the energy barrier alignment for charge transport. The theoretical model developed for this work confirms all the experimental observations.
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| 16. |
- Aziz, Shazed, et al.
(författare)
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Plant-Like Tropisms in Artificial Muscles
- 2023
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095.
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Tidskriftsartikel (refereegranskat)abstract
- Helical plants have the ability of tropisms to respond to natural stimuli, and biomimicry of such helical shapes into artificial muscles has been vastly popular. However, the shape-mimicked actuators only respond to artificially provided stimulus, they are not adaptive to variable natural conditions, thus being unsuitable for real-life applications where on-demand, autonomous operations are required. Novel artificial muscles made of hierarchically patterned helically wound yarns that are self-adaptive to environmental humidity and temperature changes are demonstrated here. Unlike shape-mimicked artificial muscles, a unique microstructural biomimicking approach is adopted, where the muscle yarns can effectively replicate the hydrotropism and thermotropism of helical plants to their microfibril level using plant-like microstructural memories. Large strokes, with rapid movement, are obtained when the individual microfilament of yarn is inlaid with hydrogel and further twisted into a coil-shaped hierarchical structure. The developed artificial muscle provides an average actuation speed of approximate to 5.2% s(-1) at expansion and approximate to 3.1% s(-1) at contraction cycles, being the fastest amongst previously demonstrated actuators of similar type. It is demonstrated that these muscle yarns can autonomously close a window in wet climates. The building block yarns are washable without any material degradation, making them suitable for smart, reusable textile and soft robotic devices.
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| 17. |
- Bao, Chunxiong, et al.
(författare)
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High Performance and Stable All-Inorganic Metal Halide Perovskite-Based Photodetectors for Optical Communication Applications
- 2018
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 30:38
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Tidskriftsartikel (refereegranskat)abstract
- Photodetectors are critical parts of an optical communication system for achieving efficient photoelectronic conversion of signals, and the response speed directly determines the bandwidth of the whole system. Metal halide perovskites, an emerging class of low-cost solution-processed semiconductors, exhibiting strong optical absorption, low trap states, and high carrier mobility, are widely investigated in photodetection applications. Herein, through optimizing the device engineering and film quality, high-performance photodetectors based on all-inorganic cesium lead halide perovskite (CsPbIxBr3-x), which simultaneously possess high sensitivity and fast response, are demonstrated. The optimized devices processed from CsPbIBr2 perovskite show a practically measured detectable limit of about 21.5 pW cm(-2) and a fast response time of 20 ns, which are both among the highest reported device performance of perovskite-based photodetectors. Moreover, the photodetectors exhibit outstanding long-term environmental stability, with negligible degradation of the photoresponse property after 2000 h under ambient conditions. In addition, the resulting perovskite photodetector is successfully integrated into an optical communication system and its applications as an optical signal receiver on transmitting text and audio signals is demonstrated. The results suggest that all-inorganic metal halide perovskite-based photodetectors have great application potential for optical communication.
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| 18. |
- Bao, Jiming, et al.
(författare)
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Nanowire-induced Wurtzite InAs Thin Film on Zinc-Blende InAs Substrate
- 2009
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Ingår i: Advanced Materials. - : Wiley. - 1521-4095 .- 0935-9648. ; 21:36, s. 3654-3654
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Tidskriftsartikel (refereegranskat)abstract
- InAs pyramids and platelets on a zinc-blende InAs substrate are found to exhibit a wurtzite crystal structure. induced by wurtzite InAs nanowires, wurtzite InAs thin film and its associated zinc-blende/wurtzite heterocrystalline heterostructures may open up new opportunities in band-gap engineering and related device applications.
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| 19. |
- Barbero, David, et al.
(författare)
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Carbon nanotube networks : nano-engineering of SWNT networks for enhanced charge transport at ultralow nanotube loading
- 2014
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Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 26:19, s. 3164-
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Tidskriftsartikel (refereegranskat)abstract
- Arrays of nano-engineered carbon nanotube networks embedded in nanoscale polymer structures enable highly efficient charge transport as demonstrated by D. R. Barbero and co-workers on page 3111. An increase in charge transport by several orders of magnitude is recorded at low nanotube loading compared to traditional random networks in either insulating (polystyrene) or semiconducting (polythiophene) polymers. These novel networks are expected to enhance the performance of next generation hybrid and carbon based photovoltaic devices.
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| 20. |
- Barbero, David, et al.
(författare)
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Nano-engineering of SWNT networks for enhanced charge transport at ultralow nanotube loading
- 2014
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Ingår i: Advanced Materials. - : John Wiley & Sons. - 0935-9648 .- 1521-4095. ; 26:19, s. 3111-3117
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Tidskriftsartikel (refereegranskat)abstract
- We demonstrate a simple and controllable method to form periodic arrays of highly conductive nano-engineered single wall carbon nanotube networks from solution. These networks increase the conductivity of a polymer composite by as much as eight orders of magnitude compared to a traditional random network. These nano-engineered networks are demonstrated in both polystyrene and polythiophene polymers.
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| 21. |
- Barbero, David R., et al.
(författare)
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Functional single-walled carbon nanotubes and nanoengineered networks for organic- and Perovskite-solar-cell applications
- 2016
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 28:44, s. 9668-9685
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Tidskriftsartikel (refereegranskat)abstract
- Carbon nanotubes have a variety of remarkable electronic and mechanical properties that, in principle, lend them to promising optoelectronic applications. However, the field has been plagued by heterogeneity in the distributions of synthesized tubes and uncontrolled bundling, both of which have prevented nanotubes from reaching their full potential. Here, a variety of recently demonstrated solution-processing avenues is presented, which may combat these challenges through manipulation of nanoscale structures. Recent advances in polymer-wrapping of single-walled carbon nanotubes (SWNTs) are shown, along with how the resulting nanostructures can selectively disperse tubes while also exploiting the favorable properties of the polymer, such as light-harvesting ability. New methods to controllably form nanoengineered SWNT networks with controlled nanotube placement are discussed. These nanoengineered networks decrease bundling, lower the percolation threshold, and enable a strong enhancement in charge conductivity compared to random networks, making them potentially attractive for optoelectronic applications. Finally, SWNT applications, to date, in organic and perovskite photovoltaics are reviewed, and insights as to how the aforementioned recent advancements can lead to improved device performance provided.
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| 22. |
- Barriga, Hanna M. G., et al.
(författare)
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Coupling Lipid Nanoparticle Structure and Automated Single-Particle Composition Analysis to Design Phospholipase-Responsive Nanocarriers
- 2022
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 34:26
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Tidskriftsartikel (refereegranskat)abstract
- Lipid nanoparticles (LNPs) are versatile structures with tunable physicochemical properties that are ideally suited as a platform for vaccine delivery and RNA therapeutics. A key barrier to LNP rational design is the inability to relate composition and structure to intracellular processing and function. Here Single Particle Automated Raman Trapping Analysis (SPARTA) is combined with small-angle X-ray and neutron scattering (SAXS/SANS) techniques to link LNP composition with internal structure and morphology and to monitor dynamic LNP-phospholipase D (PLD) interactions. This analysis demonstrates that PLD, a key intracellular trafficking mediator, can access the entire LNP lipid membrane to generate stable, anionic LNPs. PLD activity on vesicles with matched amounts of enzyme substrate is an order of magnitude lower, indicating that the LNP lipid membrane structure can be used to control enzyme interactions. This represents an opportunity to design enzyme-responsive LNP solutions for stimuli-responsive delivery and diseases where PLD is dysregulated.
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| 23. |
- Behera, Nilamani, et al.
(författare)
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Ultra-Low Current 10 nm Spin Hall Nano-Oscillators
- 2024
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 36:5
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Tidskriftsartikel (refereegranskat)abstract
- Nano-constriction based spin Hall nano-oscillators (SHNOs) are at the forefront of spintronics research for emerging technological applications, such as oscillator-based neuromorphic computing and Ising Machines. However, their miniaturization to the sub-50 nm width regime results in poor scaling of the threshold current. Here, it shows that current shunting through the Si substrate is the origin of this problem and studies how different seed layers can mitigate it. It finds that an ultra-thin Al2O3 seed layer and SiN (200 nm) coated p-Si substrates provide the best improvement, enabling us to scale down the SHNO width to a truly nanoscopic dimension of 10 nm, operating at threshold currents below 30 (Formula presented.) A. In addition, the combination of electrical insulation and high thermal conductivity of the Al2O3 seed will offer the best conditions for large SHNO arrays, avoiding any significant temperature gradients within the array. The state-of-the-art ultra-low operational current SHNOs hence pave an energy-efficient route to scale oscillator-based computing to large dynamical neural networks of linear chains or 2Darrays.
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| 24. |
- Benselfelt, Tobias, et al.
(författare)
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Electrochemically Controlled Hydrogels with Electrotunable Permeability and Uniaxial Actuation
- 2023
-
Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 35:45
-
Tidskriftsartikel (refereegranskat)abstract
- The unique properties of hydrogels enable the design of life-like soft intelligent systems. However, stimuli-responsive hydrogels still suffer from limited actuation control. Direct electronic control of electronically conductive hydrogels can solve this challenge and allow direct integration with modern electronic systems. An electrochemically controlled nanowire composite hydrogel with high in-plane conductivity that stimulates a uniaxial electrochemical osmotic expansion is demonstrated. This materials system allows precisely controlled shape-morphing at only -1 V, where capacitive charging of the hydrogel bulk leads to a large uniaxial expansion of up to 300%, caused by the ingress of & AP;700 water molecules per electron-ion pair. The material retains its state when turned off, which is ideal for electrotunable membranes as the inherent coupling between the expansion and mesoporosity enables electronic control of permeability for adaptive separation, fractionation, and distribution. Used as electrochemical osmotic hydrogel actuators, they achieve an electroactive pressure of up to 0.7 MPa (1.4 MPa vs dry) and a work density of & AP;150 kJ m-3 (2 MJ m-3 vs dry). This new materials system paves the way to integrate actuation, sensing, and controlled permeation into advanced soft intelligent systems. The unique properties of hydrogels enable the design of life-like soft intelligent systems. This work demonstrates how the swelling of hydrogels from cellulose nanofibrils and carbon nanotubes can be electrochemically controlled to achieve electrochemical osmotic actuation. This new materials system paves the way for integrated actuation, sensing, and controlled permeation in electrotunable separation membranes or soft actuators.image
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| 25. |
- Benselfelt, Tobias, et al.
(författare)
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Electrochemically Controlled Hydrogels with Electrotunable Permeability and Uniaxial Actuation
- 2023
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 35:45
-
Tidskriftsartikel (refereegranskat)abstract
- The unique properties of hydrogels enable the design of life-like soft intelligent systems. However, stimuli-responsive hydrogels still suffer from limited actuation control. Direct electronic control of electronically conductive hydrogels can solve this challenge and allow direct integration with modern electronic systems. An electrochemically controlled nanowire composite hydrogel with high in-plane conductivity that stimulates a uniaxial electrochemical osmotic expansion is demonstrated. This materials system allows precisely controlled shape-morphing at only −1 V, where capacitive charging of the hydrogel bulk leads to a large uniaxial expansion of up to 300%, caused by the ingress of ≈700 water molecules per electron–ion pair. The material retains its state when turned off, which is ideal for electrotunable membranes as the inherent coupling between the expansion and mesoporosity enables electronic control of permeability for adaptive separation, fractionation, and distribution. Used as electrochemical osmotic hydrogel actuators, they achieve an electroactive pressure of up to 0.7 MPa (1.4 MPa vs dry) and a work density of ≈150 kJ m−3 (2 MJ m−3 vs dry). This new materials system paves the way to integrate actuation, sensing, and controlled permeation into advanced soft intelligent systems.
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| 26. |
- Berggren, Magnus, et al.
(författare)
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Browsing the Real World using Organic Electronics, Si-Chips, and a Human Touch
- 2016
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 28:10, s. 1911-1916
-
Tidskriftsartikel (refereegranskat)abstract
- Two different e-labels were developed to explore the feasibility and to identify scientifi c and engineering challenges of the Real-World-Web platform. First was a printed biosensor e-label, comprising Si-chips with an array of different printegrated devices, and second, an e-label to explore the feasibility of transferring data, through the human body, between a mobile device and different distributed e-labels, adhered onto the body or onto dedicated devices and surfaces of one's ambience. The silicon chips utilized in e-labels, include analogue and digital circuitry to receive and handle sensory input, to perform signal processing, and to transmit information to antennas and displays. When used, the e-label is turned on, and a sample is then added onto the sensor area. The display provides simple instructions and updated information to the user. All data handling, electrical probing, and analysis of the sensor is performed by the Si-chips, and the sensing data is finally shown in the printed display. The second e-label exemplifies an ID-tag for body area networks (BAN) communication applications, which, in part, is manufactured and integrated in the same way as the first e-label, but with another choice of Si-chips and capacitive antennas.
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| 27. |
- Berggren, Magnus, et al.
(författare)
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Green Electroluminescence in Poly-(3-cyclohexylthiophene) light-emitting diodes
- 1994
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Ingår i: Advanced Materials. - : Wiley-VCH Verlag Berlin. - 0935-9648 .- 1521-4095. ; 6:6, s. 488-490
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Tidskriftsartikel (refereegranskat)abstract
- Electoluminescent devices based on polythiophene-system this films have been demonstrated that together span the entire visible range, steric hindrance being used to vary the bandgap between compunds. Poly-(3-cyclohexylthiophene), see Figures, exhibits green electoluminescence. Possible interpretations of this observation are proposed.
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| 28. |
- Berggren, Magnus, et al.
(författare)
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Ion Electron-Coupled Functionality in Materials and Devices Based on Conjugated Polymers
- 2019
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Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 31:22
-
Forskningsöversikt (refereegranskat)abstract
- The coupling between charge accumulation in a conjugated polymer and the ionic charge compensation, provided from an electrolyte, defines the mode of operation in a vast array of different organic electrochemical devices. The most explored mixed organic ion-electron conductor, serving as the active electrode in these devices, is poly(3,4-ethyelenedioxythiophene) doped with polystyrelensulfonate (PEDOT:PSS). In this progress report, scientists of the Laboratory of Organic Electronics at Linkoping University review some of the achievements derived over the last two decades in the field of organic electrochemical devices, in particular including PEDOT:PSS as the active material. The recently established understanding of the volumetric capacitance and the mixed ion-electron charge transport properties of PEDOT are described along with examples of various devices and phenomena utilizing this ion-electron coupling, such as the organic electrochemical transistor, ionic-electronic thermodiffusion, electrochromic devices, surface switches, and more. One of the pioneers in this exciting research field is Prof. Olle Inganas and the authors of this progress report wish to celebrate and acknowledge all the fantastic achievements and inspiration accomplished by Prof. Inganas all since 1981.
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| 29. |
- Berggren, Magnus, et al.
(författare)
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Organic bioelectronics
- 2007
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 19:20, s. 3201-3213
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Forskningsöversikt (refereegranskat)abstract
- During the last two decades, organic electroactive materials have been explored as the working material in a vast array of electronic devices, promising low-cost, flexible, and easily manufactured systems. The same materials also possess features that make them unique in bioelectronics applications, where electronic signals are translated into biosignals and vice versa. Here we review, in the broadest sense, the field of organic bioelectronics, describing the electronic properties and mechanisms of the organic electronic materials that are utilized in specific biological experiments.
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| 30. |
- Berggren, Magnus, et al.
(författare)
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Solid-state droplet laser made from an organic blend with a conjugated polymer emitter
- 1997
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Ingår i: Advanced Materials. - : Wiley-VCH Verlag Berlin. - 0935-9648 .- 1521-4095. ; 9:12, s. 968-
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Tidskriftsartikel (refereegranskat)abstract
- Lasers based on organic materials have been produced with a wide range of resonator design and in a variety of geometries. A new strategy is presented for fabricating permanently near-spherical whispering gallery mode (WGM) lasers from a blend of PPV7 and PBD (see Figure) by a melting and resolidification process. The thresholds and quality factors of these resonators are estimated and discussed.
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| 31. |
- Berggren, Magnus, et al.
(författare)
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Ultraviolet electroluminescence from an organic light emitting diode
- 1995
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Ingår i: Advanced Materials. - : Wiley-VCH Verlag Berlin. - 0935-9648 .- 1521-4095. ; 7:11, s. 900-903
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Tidskriftsartikel (refereegranskat)abstract
- The extension of the emission region for organic LEDs into the ultraviolet region is reported. Emission at 394 nm is achieved by modifying the geometry of a device based on poly(octylphenyl)bithiophene (PTOPT) and poly(octylphenyl)oxadiazole (PBD) which had previously been shown to emit white light. Through changing the geometry the red and green emission peaks have been suppressed and the UV band (from the PBD) enhanced.
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| 32. |
- Berglund, Lars, 1979-, et al.
(författare)
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Bioinspired Wood Nanotechnology for Functional Materials
- 2018
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 30:19
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Tidskriftsartikel (refereegranskat)abstract
- It is a challenging task to realize the vision of hierarchically structured nanomaterials for large-scale applications. Herein, the biomaterial wood as a large-scale biotemplate for functionalization at multiple scales is discussed, to provide an increased property range to this renewable and CO2-storing bioresource, which is available at low cost and in large quantities. The Progress Report reviews the emerging field of functional wood materials in view of the specific features of the structural template and novel nanotechnological approaches for the development of wood-polymer composites and wood-mineral hybrids for advanced property profiles and new functions.
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| 33. |
- Bing, Zhao, 1990, et al.
(författare)
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Unconventional Charge–Spin Conversion in Weyl-Semimetal WTe2
- 2020
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 32:38
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Tidskriftsartikel (refereegranskat)abstract
- An outstanding feature of topological quantum materials is their novel spin topology in the electronic band structures with an expected large charge-to-spin conversion efficiency. Here, a charge-current-induced spin polarization in the type-II Weyl semimetal candidate WTe2 and efficient spin injection and detection in a graphene channel up to room temperature are reported. Contrary to the conventional spin Hall and Rashba–Edelstein effects, the measurements indicate an unconventional charge-to-spin conversion in WTe2, which is primarily forbidden by the crystal symmetry of the system. Such a large spin polarization can be possible in WTe2 due to a reduced crystal symmetry combined with its large spin Berry curvature, spin–orbit interaction with a novel spin-texture of the Fermi states. A robust and practical method is demonstrated for electrical creation and detection of such a spin polarization using both charge-to-spin conversion and its inverse phenomenon and utilized it for efficient spin injection and detection in the graphene channel up to room temperature. These findings open opportunities for utilizing topological Weyl materials as nonmagnetic spin sources in all-electrical van der Waals spintronic circuits and for low-power and high-performance nonvolatile spintronic technologies.
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| 34. |
- Bobbert, Peter A., et al.
(författare)
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Operational Stability of Organic Field-Effect Transistors
- 2012
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Ingår i: Advanced Materials. - : Wiley-VCH Verlag. - 0935-9648 .- 1521-4095. ; 24:9, s. 1146-1158
-
Tidskriftsartikel (refereegranskat)abstract
- Organic field-effect transistors (OFETs) are considered in technological applications for which low cost or mechanical flexibility are crucial factors. The environmental stability of the organic semiconductors used in OFETs has improved to a level that is now sufficient for commercialization. However, serious problems remain with the stability of OFETs under operation. The causes for this have remained elusive for many years. Surface potentiometry together with theoretical modeling provide new insights into the mechanisms limiting the operational stability. These indicate that redox reactions involving water are involved in an exchange of mobile charges in the semiconductor with protons in the gate dielectric. This mechanism elucidates the established key role of water and leads in a natural way to a universal stress function, describing the stretched exponential-like time dependence ubiquitously observed. Further study is needed to determine the generality of the mechanism and the role of other mechanisms.
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| 35. |
- Bobek, Thomas, et al.
(författare)
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Self-organized hexagonal patterns of independent magnetic nanodots
- 2007
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 19:24, s. 4375-
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Tidskriftsartikel (refereegranskat)abstract
- A method for producing self-organised arrays of nanometric metallic dots is reported. It consists on developing first the nanodot pattern by ion erosion on a semiconductor cover film and transferring it to a previously buried metallic layer. This procedure has been applied to Co, and the ferromagnetic behaviour of the dots at room temperature is demonstrated.
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| 36. |
- Bohme, O, et al.
(författare)
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Nanoparticles as the active element of high-temperature metal-insulator-silicon carbide gas sensors
- 2001
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Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 13:8, s. 597-
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Tidskriftsartikel (refereegranskat)abstract
- The sensor performance of MISiC (metal-insulator-silicon carbide) diode devices depends on their temperature pretreatment: an activation step at 600 degreesC leads to fast-responding devices with extraordinarily high signals but the devices fail when operated above 700 degreesC. The authors focus on the key role of nanoparticles in high-temperature gas sensor applications of these MISiC devices, presenting a model in which the interface dipole moment of nanoparticles is seen as the driving force and explaining the difference in response of capacitor-configuration and Schottky-diode-configuration devices.
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| 37. |
- Bolin, Maria, et al.
(författare)
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Active Control of Epithelial Cell-Density Gradients Grown Along the Channel of an Organic Electrochemical Transistor
- 2009
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Ingår i: ADVANCED MATERIALS. - : Wiley. - 0935-9648 .- 1521-4095. ; 21:43, s. 4379-
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Tidskriftsartikel (refereegranskat)abstract
- Complex patterning of the extracellular matrix, cells, and tissues under in situ electronic control is the aim of the technique presented here. The distribution of epithelial cells along the channel of an organic electrochemical transistor is shown to be actively controlled by the gate and drain voltages, as electrochemical gradients are formed along the transistor channel when the device is biased.
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| 38. |
- Boström, Hanna L. B., et al.
(författare)
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How Reproducible is the Synthesis of Zr-Porphyrin Metal-Organic Frameworks? An Interlaboratory Study
- 2024
-
Ingår i: Advanced Materials. - 0935-9648 .- 1521-4095. ; 36:15
-
Tidskriftsartikel (refereegranskat)abstract
- Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building blocks, which complicates the phase selectivity. Likewise, the high sensitivity to slight changes in synthesis conditions may cause reproducibility issues. This is crucial, as it hampers the research and commercialization of affected MOFs. Here, it presents the first-ever interlaboratory study of the synthetic reproducibility of two Zr-porphyrin MOFs, PCN-222 and PCN-224, to investigate the scope of this problem. For PCN-222, only one sample out of ten was phase pure and of the correct symmetry, while for PCN-224, three are phase pure, although none of these show the spatial linker order characteristic of PCN-224. Instead, these samples resemble dPCN-224 (disordered PCN-224), which has recently been reported. The variability in thermal behavior, defect content, and surface area of the synthesised samples are also studied. The results have important ramifications for field of metal-organic frameworks and their crystallization, by highlighting the synthetic challenges associated with a multi-variable synthesis space and flat energy landscapes characteristic of MOFs. It performed an interlaboratory study of the synthesis of the metal-organic frameworks (MOFs) PCN-222 and PCN-224. Ten participants independently synthesized the two MOFs and the products are analyzed, primarily by X-ray diffraction. The success rates are low (one-three samples corresponding to a pure sample of the correct phase), thus highlighting the problems with irreproducibility in MOF synthesis. image
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| 39. |
- Boxberg, Fredrik, et al.
(författare)
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Elastic and Piezoelectric Properties of Zincblende and Wurtzite Crystalline Nanowire Heterostructures.
- 2012
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Ingår i: Advanced Materials. - : Wiley. - 1521-4095 .- 0935-9648. ; 24:34, s. 4692-4706
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Tidskriftsartikel (refereegranskat)abstract
- The elastic and piezoelectric properties of zincblende and wurtzite crystalline InAs/InP nanowire heterostructures have been studied using electro-elastically coupled continuum elasticity theory. A comprehensive comparison of strains, piezoelectric potentials and piezoelectric fields in the two crystal types of nanowire heterostructures is presented. For each crystal type, three different forms of heterostructures-core-shell, axial superlattice, and quantum dot nanowire heterostructures-are considered. In the studied nanowire heterostructures, the principal strains are found to be insensitive to the change in the crystal structure. However, the shear strains in the zincblende and wurtzite nanowire heterostructures can be very different. All the studied nanowire heterostructures are found to exhibit a piezoelectric field along the nanowire axis. The piezoelectric field is in general much stronger in a wurtzite nanowire heterostructure than in its corresponding zincblende heterostructure. Our results are expected to be particularly important for analyzing and understanding the properties of epitaxially grown nanowire heterostructures and for applications in nanowire electronics, optoelectronics, and biochemical sensing.
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| 40. |
- Braun, Slawomir, et al.
(författare)
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Energy-Level Alignment at Organic/Metal and Organic/Organic Interfaces
- 2009
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Ingår i: ADVANCED MATERIALS. - : Wiley. - 0935-9648 .- 1521-4095. ; 21:14-15, s. 1450-1472
-
Forskningsöversikt (refereegranskat)abstract
- In this Review, we summarize recent work on modeling of organic/metal and organic/organic interfaces. Some of the models discussed have a semiempirical approach, that is, experimentally derived values are used in combination with theory, and others rely completely of calculations. The models are categorized according to the types of interfaces they apply to, and the strength of the interaction at the interface has been used as the main factor. We explain the basics of the models, their use, and give examples on how the models correlate with experimental results. We stress that given the complexity of organic/metal and organic/organic interface formation, it is crucial to know the exact way in which the interface was formed before choosing the model that is applicable, as none of the models presented covers the whole range of interface interaction strengths (weak physisorption to strong chemisorption).
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| 41. |
- Camacho, Rafael, et al.
(författare)
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Fluorescence Anisotropy Reloaded—Emerging Polarization Microscopy Methods for Assessing Chromophores' Organization and Excitation Energy Transfer in Single Molecules, Particles, Films, and Beyond
- 2019
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Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 31:22
-
Forskningsöversikt (refereegranskat)abstract
- Fluorescence polarization is widely used to assess the orientation/rotation of molecules, and the excitation energy transfer between closely located chromophores. Emerging since the 1990s, single molecule fluorescence spectroscopy and imaging stimulate the application of light polarization for studying molecular organization and energy transfer beyond ensemble averaging. Here, traditional fluorescence polarization and linear dichroism methods used for bulk samples are compared with techniques specially developed for, or inspired by, single molecule fluorescence spectroscopy. Techniques for assessing energy transfer in anisotropic samples, where the traditional fluorescence anisotropy framework is not readily applicable, are discussed in depth. It is shown that the concept of a polarization portrait and the single funnel approximation can lay the foundation for alternative energy transfer metrics. Examples ranging from fundamental studies of photoactive materials (conjugated polymers, light-harvesting aggregates, and perovskite semiconductors) to Förster resonant energy transfer (FRET)-based biomedical imaging are presented. Furthermore, novel uses of light polarization for super-resolution optical imaging are mentioned as well as strategies for avoiding artifacts in polarization microscopy.
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| 42. |
- Campana, Alessandra, et al.
(författare)
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Electrocardiographic recording with conformable organic electrochemical transistor fabricated on resorbable bioscaffold
- 2014
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Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 26:23, s. 3874-3878
-
Tidskriftsartikel (refereegranskat)abstract
- Organic electrochemical transistors are fabricated on a poly(L-lactide-co-glycolide) substrate. Fast and sensitive performance of the transistors allows recording of the electrocardiogram. The result paves the way for new types of bioelectronic interfaces with reduced invasiveness due to bioresorption and soft mechanical properties.
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| 43. |
- Cao, Danfeng, 1991-, et al.
(författare)
-
Biohybrid Variable-Stiffness Soft Actuators that Self-Create Bone
- 2022
-
Ingår i: Advanced Materials. - Weinheim, Germany : Wiley-VCH Verlag GmbH & Co. KGaA. - 0935-9648 .- 1521-4095. ; 34:8
-
Tidskriftsartikel (refereegranskat)abstract
- Inspired by the dynamic process of initial bone development, in which a soft tissue turns into a solid load-bearing structure, the fabrication, optimization, and characterization of bioinduced variable-stiffness actuators that can morph in various shapes and change their properties from soft to rigid are hereby presented. Bilayer devices are prepared by combining the electromechanically active properties of polypyrrole with the compliant behavior of alginate gels that are uniquely functionalized with cell-derived plasma membrane nanofragments (PMNFs), previously shown to mineralize within 2 days, which promotes the mineralization in the gel layer to achieve the soft to stiff change by growing their own bone. The mineralized actuator shows an evident frozen state compared to the movement before mineralization. Next, patterned devices show programmed directional and fixated morphing. These variable-stiffness devices can wrap around and, after the PMNF-induced mineralization in and on the gel layer, adhere and integrate onto bone tissue. The developed biohybrid variable-stiffness actuators can be used in soft (micro-)robotics and as potential tools for bone repair or bone tissue engineering.
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| 44. |
- Cao, Fangcheng, et al.
(författare)
-
Recent Advances in Oxidation Stable Chemistry of 2D MXenes
- 2022
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Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 34:13
-
Forskningsöversikt (refereegranskat)abstract
- As an emerging star of 2D nanomaterials, 2D transition metal carbides and nitrides, named MXenes, present a large potential in various research areas owing to their intrinsic multilayer structure and intriguing physico-chemical properties. However, the fabrication and application of functional MXene-based devices still remain challenging as they are prone to oxidative degradation under ambient environment. Within this review, the preparation methods of MXenes focusing on the recent investigations on their thermal structure-stability relationships in inert, oxidizing, and aqueous environments are systematically introduced. Moreover, the key factors that affect the oxidation of MXenes, such as, atmosphere, temperature, composition, microstructure, and aqueous environment, are reviewed. Based on different scenarios, strategies for avoiding or delaying the oxidation of MXenes are proposed to encourage the utilization of MXenes in complicated environments, especially at high temperature. Furthermore, the chemistry of MXene-derived oxides is analyzed, which can offer perspectives on the further design and fabrication of novel 2D composites with the unique structures of MXenes being preserved.
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| 45. |
- Carlos, L. D., et al.
(författare)
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Nanoscopic photoluminescence memory as a fingerprint of complexity in self-assembled alkyl/siloxane hybrids
- 2007
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 19:3, s. 341-348
-
Tidskriftsartikel (refereegranskat)abstract
- A thermally activated photoluminescence memory effect, induced by a reversible order-disorder phase transition of the alkyl chains, is reported for highly organized bilayer alkyl/siloxane hybrids (see figure; left at room temperature, right at 120 degrees C). The emission energy is sensitive to the annihilation/formation of the hydrogen-bonded amide-amide array displaying a unique nanoscopic sensitivity (ca. 150 nm).
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| 46. |
- Chae, Soosang, et al.
(författare)
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Stretchable Thin Film Mechanical-Strain-Gated Switches and Logic Gate Functions Based on a Soft Tunneling Barrier
- 2021
-
Ingår i: Advanced Materials. - : Wiley-Blackwell. - 0935-9648 .- 1521-4095. ; 33:41
-
Tidskriftsartikel (refereegranskat)abstract
- Mechanical-strain-gated switches are cornerstone components of material-embedded circuits that perform logic operations without using conventional electronics. This technology requires a single material system to exhibit three distinct functionalities: strain-invariant conductivity and an increase or decrease of conductivity upon mechanical deformation. Herein, mechanical-strain-gated electric switches based on a thin-film architecture that features an insulator-to-conductor transition when mechanically stretched are demonstrated. The conductivity changes by nine orders of magnitude over a wide range of tunable working strains (as high as 130%). The approach relies on a nanometer-scale sandwiched bilayer Au thin film with an ultrathin poly(dimethylsiloxane) elastomeric barrier layer; applied strain alters the electron tunneling currents through the barrier. Mechanical-force-controlled electric logic circuits are achieved by realizing strain-controlled basic (AND and OR) and universal (NAND and NOR) logic gates in a single system. The proposed material system can be used to fabricate material-embedded logics of arbitrary complexity for a wide range of applications including soft robotics, wearable/implantable electronics, human-machine interfaces, and Internet of Things.
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| 47. |
- Chang, Jian, 1990-, et al.
(författare)
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Tailor-Made White Photothermal Fabrics : A Bridge between Pragmatism and Aesthetic
- 2023
-
Ingår i: Advanced Materials. - : Wiley. - 0935-9648 .- 1521-4095. ; 35:41
-
Tidskriftsartikel (refereegranskat)abstract
- Maintaining human thermal comfort in the cold outdoors is crucial for diverse outdoor activities, e.g., sports and recreation, healthcare, and special occupations. To date, advanced clothes are employed to collect solar energy as a heat source to stand cold climates, while their dull dark photothermal coating may hinder pragmatism in outdoor environments and visual sense considering fashion. Herein, tailor-made white webs with strong photothermal effect are proposed. With the embedding of cesium–tungsten bronze (CsxWO3) nanoparticles (NPs) as additive inside nylon nanofibers, these webs are capable of drawing both near-infrared (NIR) and ultraviolet (UV) light in sunlight for heating. Their exceptional photothermal conversion capability enables 2.5–10.5 °C greater warmth than that of a commercial sweatshirt of six times greater thickness under different climates. Remarkably, this smart fabric can increase its photothermal conversion efficiency in a wet state. It is optimal for fast sweat or water evaporation at human comfort temperature (38.5 °C) under sunlight, and its role in thermoregulation is equally important to avoid excess heat loss in wilderness survival. Obviously, this smart web with considerable merits of shape retention, softness, safety, breathability, washability, and on-demand coloration provides a revolutionary solution to realize energy-saving outdoor thermoregulation and simultaneously satisfy the needs of fashion and aesthetics.
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| 48. |
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| 49. |
- Chen, Desui, et al.
(författare)
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Shelf-Stable Quantum-Dot Light-Emitting Diodes with High Operational Performance
- 2020
-
Ingår i: Advanced Materials. - : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 32
-
Tidskriftsartikel (refereegranskat)abstract
- Quantum-dot light-emitting diodes (QLEDs) promise a new generation of high-performance, large-area, and cost-effective electroluminescent devices for both display and solid-state lighting technologies. However, a positive ageing process is generally required to improve device performance for state-of-the-art QLEDs. Here, it is revealed that the in situ reactions induced by organic acids in the commonly used encapsulation acrylic resin lead to positive ageing and, most importantly, the progression of in situ reactions inevitably results in negative ageing, i.e., deterioration of device performance after long-term shelf storage. In-depth mechanism studies focusing on the correlations between the in situ chemical reactions and the shelf-ageing behaviors of QLEDs inspire the design of an electron-transporting bilayer, which delivers both improved electrical conductivity and suppressed interfacial exciton quenching. This material innovation enables red QLEDs exhibiting neglectable changes of external quantum efficiency (>20.0%) and ultralong operational lifetime (T-95: 5500 h at 1000 nits) after storage for 180 days. This work provides design principles for oxide electron-transporting layers to realize shelf-stable and high-operational-performance QLEDs, representing a new starting point for both fundamental studies and practical applications.
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| 50. |
- Chen, Haiyang, et al.
(författare)
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Heterogeneous Nucleating Agent for High-Boiling-Point Nonhalogenated Solvent-Processed Organic Solar Cells and Modules
- 2024
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095.
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Tidskriftsartikel (refereegranskat)abstract
- High-boiling-point nonhalogenated solvents are superior solvents to produce large-area organic solar cells (OSCs) in industry because of their wide processing window and low toxicity; while, these solvents with slow evaporation kinetics will lead excessive aggregation of state-of-the-art small molecule acceptors (e.g. L8-BO), delivering serious efficiency losses. Here, a heterogeneous nucleating agent strategy is developed by grafting oligo (ethylene glycol) side-chains on L8-BO (BTO-BO). The formation energy of the obtained BTO-BO; while, changing from liquid in a solvent to a crystalline phase, is lower than that of L8-BO irrespective of the solvent type. When BTO-BO is added as the third component into the active layer (e.g. PM6:L8-BO), it easily assembles to form numerous seed crystals, which serve as nucleation sites to trigger heterogeneous nucleation and increase nucleation density of L8-BO through strong hydrogen bonding interactions even in high-boiling-point nonhalogenated solvents. Therefore, it can effectively suppress excessive aggregation during growth, achieving ideal phase-separation active layer with small domain sizes and high crystallinity. The resultant toluene-processed OSCs exhibit a record power conversion efficiency (PCE) of 19.42% (certificated 19.12%) with excellent operational stability. The strategy also has superior advantages in large-scale devices, showing a 15.03-cm2 module with a record PCE of 16.35% (certificated 15.97%). The heterogeneous nucleating agent (BTO-BO) is developed to suppress the excessive aggregation of L8-BO in high-boiling-point nonhalogenated solvents processing, achieving the active layer with high crystallinity and nano-scaled phase separation morphology. The resultant OSCs achieve record power conversion efficiencies of 19.42% (0.062-cm2) and 16.35% (15. 03-cm2) with excellent operational stabilities. image
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