| 1. |
- Li, Zaifang, et al.
(författare)
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A Free-Standing High-Output Power Density Thermoelectric Device Based on Structure-Ordered PEDOT:PSS
- 2018
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Ingår i: Advanced Electronic Materials. - : Wiley-VCH Verlagsgesellschaft. - 2199-160X. ; 4:2
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Tidskriftsartikel (refereegranskat)abstract
- A free-standing high-output power density polymeric thermoelectric (TE) device is realized based on a highly conductive (approximate to 2500 S cm(-1)) structure-ordered poly(3,4-ethylenedioxythiophene):polystyrene sulfonate film (denoted as FS-PEDOT:PSS) with a Seebeck coefficient of 20.6 mu V K-1, an in-plane thermal conductivity of 0.64 W m(-1) K-1, and a peak power factor of 107 mu W K-2 m(-1) at room temperature. Under a small temperature gradient of 29 K, the TE device demonstrates a maximum output power density of 99 +/- 18.7 mu W cm(-2), which is the highest value achieved in pristine PEDOT:PSS based TE devices. In addition, a fivefold output power is demonstrated by series connecting five devices into a flexible thermoelectric module. The simplicity of assembling the films into flexible thermoelectric modules, the low out-of-plane thermal conductivity of 0.27 W m(-1) K-1, and free-standing feature indicates the potential to integrate the FS-PEDOT:PSS TE modules with textiles to power wearable electronics by harvesting human bodys heat. In addition to the high power factor, the high thermal stability of the FS-PEDOT:PSS films up to 250 degrees C is confirmed by in situ temperature-dependent X-ray diffraction and grazing incident wide angle X-ray scattering, which makes the FS-PEDOT:PSS films promising candidates for thermoelectric applications.
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| 2. |
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| 3. |
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| 4. |
- De, Swati, et al.
(författare)
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Exciton Dynamics in Alternating Polyfluorene/Fullerene Blends
- 2008
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Ingår i: Journal of Chemical Physics. - College Park, MD, United States : American Institute of Physics (AIP). - 0021-9606 .- 1089-7690. ; 350:1-3, s. 14-22
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Tidskriftsartikel (refereegranskat)abstract
- Exciton dynamics in alternating copolymer/fullerene solar cell blends have been investigated using femtosecond transient absorption spectroscopy. The acceptor concentrations have been varied over a wide range. Experimental data, kinetic modeling and simulations, all indicate that the efficiency of exciton conversion to charges is 100% even at acceptor concentrations as low as 20 wt%. The reported dependence of solar cell efficiency on fullerene concentration may thus arise from other factors. However, there exists an acceptor concentration threshold (5 wt%) below which a substantial fraction of the excitations remain unquenched. The results, we believe are very relevant to optimization of performance efficiency by clever manipulation of morphology. We have also observed exciton–exciton energy transfer in these blends at low acceptor concentrations.
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| 5. |
- De, Swati, et al.
(författare)
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Geminate charge recombination in alternating polyfluorene copolymer/fullerene blends
- 2007
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 129:27, s. 8466-8472
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Tidskriftsartikel (refereegranskat)abstract
- By measuring excited state and charge dynamics in blends of an alternating polyfluorene copolymer and fullerene derivative over nine orders in time and two orders in light intensity, we have monitored the light-induced processes from ultrafast charge photogeneration to much slower decay of charges by recombination. We find that at low light intensities relevant to solar cell operation relatively fast (∼30 ns) geminate recombination is the dominating charge decay process, while nongeminate recombination has a negligible contribution. The conclusion of our work is that under solar illumination conditions geminate recombination of charges may be directly competing with efficient charge collection in polymer/fullerene solar cells. © 2007 American Chemical Society.
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| 6. |
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| 7. |
- Hultmark, Sandra, 1994, et al.
(författare)
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Suppressing Co-Crystallization of Halogenated Non-Fullerene Acceptors for Thermally Stable Ternary Solar Cells
- 2020
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-3028 .- 1616-301X. ; 30:48
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Tidskriftsartikel (refereegranskat)abstract
- While photovoltaic blends based on non-fullerene acceptors are touted for their thermal stability, this type of acceptor tends to crystallize, which can result in a gradual decrease in photovoltaic performance and affects the reproducibility of the devices. Two halogenated indacenodithienothiophene-based acceptors that readily co-crystallize upon mixing are studied, which indicates that the use of an acceptor mixture alone does not guarantee the formation of a disordered mixture. The addition of the donor polymer to the acceptor mixture readily suppresses the crystallization, which results in a fine-grained ternary blend with nanometer-sized domains that do not coarsen due to a high Tg ≈ 200 °C. As a result, annealing at temperatures of up to 170 °C does not markedly affect the photovoltaic performance of ternary devices, in contrast to binary devices that suffer from acceptor crystallization in the active layer. The results indicate that the ternary approach enables the use of high-temperature processing protocols, which are needed for upscaling and high-throughput fabrication of organic solar cells. Further, ternary devices display a stable photovoltaic performance at 130 °C for at least 205 h, which indicates that the use of acceptor mixtures allows to fabricate devices with excellent thermal stability.
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| 8. |
- Inganäs, Olle, 1951-, et al.
(författare)
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Alternating fluorene copolymer/fullerene blend solar cells
- 2005. - 1
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Ingår i: Organic Photovoltaics. - Boca Raton, FL, USA : CRC Press. - 082475963X - 9780824759636 ; , s. 387-402
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Recently developed organic photovoltaics (OPVs) show distinct advantages over their inorganic counterparts due to their lighter weight, flexible shape, versatile materials synthesis and device fabrication schemes, and low cost in large-scale industrial production. Although many books currently exist on general concepts of PV and inorganic PV materials and devices, few are available that offer a comprehensive overview of recently fast developing organic and polymeric PV materials and devices.Organic Photovoltaics: Mechanisms, Materials, and Devicesfills this gap. The book provides an international perspective on the latest research in this rapidly expanding field with contributions from top experts around the world. It presents a unified approach comprising three sections: General Overviews; Mechanisms and Modeling; and Materials and Devices. Discussions include sunlight capture, exciton diffusion and dissociation, interface properties, charge recombination and migration, and a variety of currently developing OPV materials/devices. The book also includes two forewords: one by Nobel Laureate Dr. Alan J. Heeger, and the other by Drs. Aloysius Hepp and Sheila Bailey of NASA Glenn Research Center.Organic Photovoltaics equips students, researchers, and engineers with knowledge of the mechanisms, materials, devices, and applications of OPVs necessary to develop cheaper, lighter, and cleaner renewable energy throughout the coming decades.
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| 9. |
- Jespersen, Kim, et al.
(författare)
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Charge formation and transport in bulk-heterojunction solar cells based on alternating polyfluorene copolymers blended with fullerenes
- 2006
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Ingår i: Organic Electronics. - : Elsevier BV. - 1566-1199 .- 1878-5530. ; 7:4, s. 235-242
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Tidskriftsartikel (refereegranskat)abstract
- We investigate charge formation in bulk-heterojunction solar cells based on conjugated polymers in the form of alternating polyfluorene copolymers and the methanofullerene PCBM. Using transient absorption spectroscopy we show that optimal charge formation is obtained with 20-50 wt% PCBM. This is in contrast to the maximum short circuit current density obtained at similar to 80 wt% PCBM as determined by steady state current density-voltage characterization. Hence, we show explicitly that the solar cell performance of these interpenetrating polymer networks containing PCBM is limited by charge transport rather than by formation of charges. (c) 2006 Elsevier B.V. All rights reserved.
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| 10. |
- Jiang, Qinglin, et al.
(författare)
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High Thermoelectric Performance in n-Type Perylene Bisimide Induced by the Soret Effect
- 2020
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Ingår i: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 32:45
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Tidskriftsartikel (refereegranskat)abstract
- Low-cost, non-toxic, abundant organic thermoelectric materials are currently under investigation for use as potential alternatives for the production of electricity from waste heat. While organic conductors reach electrical conductivities as high as their inorganic counterparts, they suffer from an overall low thermoelectric figure of merit (ZT) due to their small Seebeck coefficient. Moreover, the lack of efficient n-type organic materials still represents a major challenge when trying to fabricate efficient organic thermoelectric modules. Here, a novel strategy is proposed both to increase the Seebeck coefficient and achieve the highest thermoelectric efficiency for n-type organic thermoelectrics to date. An organic mixed ion-electron n-type conductor based on highly crystalline and reduced perylene bisimide is developed. Quasi-frozen ionic carriers yield a large ionic Seebeck coefficient of -3021 mu V K-1, while the electronic carriers dominate the electrical conductivity which is as high as 0.18 S cm(-1)at 60% relative humidity. The overall power factor is remarkably high (165 mu W m(-1)K(-2)), with aZT= 0.23 at room temperature. The resulting single leg thermoelectric generators display a high quasi-constant power output. This work paves the way for the design and development of efficient organic thermoelectrics by the rational control of the mobility of the electronic and ionic carriers.
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| 11. |
- Jin, Yingzhi, 1991-
(författare)
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Organic electronic devices for solar energy conversion and storage
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on two types of organic electronic devices: organic photovoltaic (OPV) devices for solar energy conversion, and photo-capacitors for energy storage.OPVs have been under the focus of research for decades as an effective technique to convert solar energy to electricity. So far, the efficiency of bulk heterojunction OPV consisting donor and acceptor materials is approaching to 18% with non-fullerene acceptor (NFA), which make it close to commercialization. The process of charge generation and recombination are two competing processes in OPVs, since their requirements for the active layer morphology are contradictory. Large donor/acceptor interfaces facilitate charge generation but hinder the transporting pathways for charge transportation. The simultaneously enhanced charge generation and transportation are achieved by using the ternary strategy in my first paper. The fully mixed donors and NFAs are beneficial for the charge generation and fullerene is introduced as an extra electron transport channel. The hierarchical morphology of the blend film is confirmed by the TEM results. The voltage loss analyses indicate that the hierarchical morphology could suppress unfavorable charge transfer state and non-radiative recombination loss. In my second paper, efficient charge generation with low voltage loss are achieved in the solar cells by rational designing a series of NFAs. The detailed voltage losses are discussed in these binary systems, revealing the critical relationship between radiative efficiency and device performance.To harvest photocurrent in OPVs, long lifetime triplet excitons are highly expected to be good candidates. The potential of triplet materials in OPVs has been explored since 1970s. However, the performance of the triplet materials-based OPVs is far behind. The voltage loss in triplet OPVs is intensively studied in my third work. A higher open circuit voltage (0.88 V) is observed for Ir(FOtbpa)3-based devices than those of Ir(Ftbpa)3 (0.80 V) despite a lower charge transfer state energy. To understand above result, the voltage losses through radiative and non-radiative recombination pathways in two devices are quantitively investigated, which indicate a reduced non-radiative recombination loss in the Ir(FOtbpa)3-based devices.The fluctuation of sun irradiation resulting the unstable output power of solar cells. Therefore, it is important to store electricity of solar cells for later use. Integrated photo-capacitor (IPC), combining a solar cell and a super-capacitor by sharing one common electrode, is able to simultaneously realize the energy harvesting and storage. Building upon this advantage, IPC devices received tremendous research attention. In my fourth and last papers, we introduced super-capacitors to construct IPC devices with OPV device or modules. A free standing thick- PEDOT:PSS film is successfully integrated into an all solution-processed IPC device as the common electrode. Resulting devices demonstrate good performance and outstanding stability. With solar PV modules, a higher voltage can be generated and stored by asymmetric supercapacitors, which could be used as a portable power unit.
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| 12. |
- Jönsson, Stina, et al.
(författare)
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Photoelectron spectroscopy of the contact between the cathode and the active layers in plastic solar cells : the role of LiF
- 2005
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Ingår i: Japanese Journal of Applied Physics. - 0021-4922 .- 1347-4065. ; 44:6A, s. 3695-3701
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Tidskriftsartikel (refereegranskat)abstract
- The surfaces and electrode interfaces of a polymer blend used in prototype solar cells have been characterized with photoelectron spectroscopy. The polymer blend in question is a 1:4 mixture of APFO-3:PCBM. Based on surface analysis of the pristine film we can conclude that the surface of the blend is a 1:1 mixture of APFO-3 and PCBM. The electrode systems studied are the widely used Al and Al/LiF contacts. LiF prevents formation at the Al/organic interface of Al-organic complexes that destroy the π-conjugation. In addition to this, there are two other beneficial, thickness dependent, effects. Decomposition of LiF occurs for thin enough layers in which the LiF species are in contact with both the organic film and the Al atoms, which creates a low workfunction contact. For thicker (multi)layers, the dipole formed at the LiF/organic interface is retained as no decomposition of the LiF occurs upon Al deposition.
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| 13. |
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| 14. |
- Lindgren, L.J, et al.
(författare)
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Blue light-emitting diodes based on novel polyfluorene copolymers
- 2007
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Ingår i: Journal of Luminescence. - : Elsevier BV. - 0022-2313 .- 1872-7883. ; 122-123:1-2, s. 610-613
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Tidskriftsartikel (refereegranskat)abstract
- This study presents the synthesis and characterisation of a series of fluorene-based conjugated copolymers, together with the preparation and characterisation of the corresponding light-emitting devices. The polymers consist of alkoxyphenyl-substituted fluorene units together with different amounts of a hole-transporting triphenylamine-substituted fluorene unit: 0%, 10%, 25% and 50%. All polymers (P0, P1, P2, and P3) show high photoluminescence efficiency (ηPL) and light emission (both PL and EL) in the blue spectral region. Electrochemical studies show improved hole injection as the ratio of the triphenylamine-substituted segment is increased. The electroluminescence quantum efficiencies (EQEs) of the devices increase six times going from P0 to P1. Compared with P1, polymers P2 and P3 show lower efficiencies in devices. These findings indicate the presence of an optimal polymer composition, where balance between the charge-carrier mobilities has been reached. © 2006 Elsevier B.V. All rights reserved.
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| 15. |
- Liu, Yanfeng, et al.
(författare)
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Mo1.33C MXene-Assisted PEDOT:PSS Hole Transport Layer for High-Performance Bulk-Heterojunction Polymer Solar Cells
- 2020
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Ingår i: ACS APPLIED ELECTRONIC MATERIALS. - : AMER CHEMICAL SOC. - 2637-6113. ; 2:1, s. 163-169
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Tidskriftsartikel (refereegranskat)abstract
- Here, we report the usage of two-dimensional MXene, Mo1.33C-assisted poly(3,4-ethylene dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as an efficient hole transport layer (HTL) to construct high-efficiency polymer solar cells. The composite HTLs are prepared by mixing Mo1.33C and PEDOT:PSS aqueous solution. The conventional devices based on Mo1.33C:PEDOT:PSS exhibit an average power conversion efficiency (PCE) of 9.2%, which shows a 13% enhancement compared to the reference devices. According to the results from hole mobilities, charge extraction probabilities, steady-state photoluminescence, and atomic force microscopy, the enhanced PCE can be ascribed to the improved charge transport and extraction properties of the HTL, along with the morphological improvement of the active layer on top. This work clearly demonstrates the feasibility to combine advantages of Mo1.33C MXene and PEDOT:PSS as the promising HTL in organic photovoltaics.
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| 16. |
- Liu, Yanfeng, 1992-
(författare)
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Studying Morphology Formation and Charge Separation in Organic Solar Cells
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- We are currently living in the era of automation and artificial intelligence, which requires more energy than ever before. Meanwhile, the reduction of carbon footprint is needed for keeping the environment sustainable. Exploring green energy is crucial. Solar power is one of the green energy sources. The apparatus that converts solar energy to electricity is a solar cell. Organic solar cells (OSCs), employing organic materials absorbing solar radiation and converting to electricity have got extensive attention in the last decades due to their unique advantages like lightweight, semi-transparency, and potential industrialization. In most cases, an OSC composes of two different organic semiconductors as electron donor and acceptor to form a photoactive layer with a bulk heterojunction (BHJ) structure, and sandwiched between the electron and hole transport layers and then two electrodes. The morphology of the BHJ plays a crucial role in the device's performance, and it is a result of a complicated interplay between donor, acceptor, and solvent during the film drying from a solution. Thus, in-situ monitoring the film drying during solvent evaporation could deepen understanding of the mechanism of the morphology formation. A versatile multiple spectroscopic setup is assembled for this purpose, which can record laser scattering, steady-state photoluminescence (PL), time-resolved photoluminescence (TRPL), and white-light absorption during film formation. By comparing the drying dynamics of three different blend systems with their corresponding pristine films, we find that the blend film formation and its final morphology are more dominated by the component with a higher molecular weight. Different PL and TRPL quenching profiles between fullerene- and non-fullerene-based systems provide hints about different donor-acceptor interactions. Moreover, with the help of TRPL, the relative change of quantum yield during film formation can be calculated. Besides, this setup is also proved suitable for studying mechanisms behind device optimization processes, like the usage of solvent additives. One of the unique features of OSCs based on non-fullerene acceptors is the highly efficient hole transfer from the acceptor to the donor, sometimes even under zero or negative energetic offsets. However, in these cases the mechanism of hole transfer has not been fully understood. By studying hole transfer at the donor:acceptor interface in different material systems and device configurations, we highlight the role of electric field on the charge separation of OSCs when energetic offsets are not enough. To achieve better device performance, engineering the photoelectric properties of interfacial layers is equally essential. A good interfacial layer can facilitate carrier extraction and reduce carrier recombination. We demonstrate that adding MXenes into the PEDOT:PSS can increase the conductivity of this composite hole transport layer, without sacrificing its optical transparency and work function.
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| 17. |
- Mammo, W., et al.
(författare)
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New low band gap alternating polyfluorene copolymer-based photovoltaic cells
- 2007
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Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 91:11, s. 1010-1018
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Tidskriftsartikel (refereegranskat)abstract
- New low band gap alternating polyfluorene copolymers were synthesized for use in plastic solar cells and their optical, electrochemical, and photovoltaic characteristics were determined. These polymers incorporated fluorene units alternating with groups including electron-withdrawing (A) and electron-donating (D) groups in donor-acceptor-donor (DAD) sequence to achieve the lowering of band gaps. The HOMO-LUMO values were estimated from electrochemical studies. By varying the donor and acceptor strength and position of the solubilizing substituents, similar HOMO values were obtained. These values were also found to correlate well with the open circuit voltage (VOC) values determined from photovoltaic data of the polymers blended with the acceptor PCBM. Despite similar HOMO values, the absorption spectra of the polymers differ significantly. This prompted the preparation of photovoltaic devices consisting of blends of two polymers with complementary absorptions in combination with PCBM to harvest more photons in the polymer solar cells. © 2007 Elsevier B.V. All rights reserved.
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| 18. |
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| 19. |
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| 20. |
- Qian, Deping
(författare)
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Studies of Voltage Losses in Organic Solar Cells
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Organic photovoltaic (OPV) devices based on semiconducting polymers and small molecules are potential alternatives to inorganic solar cells, owing to their advantages of being inexpensive, lightweight, flexible and suitable for roll-to-roll production. The state of art organic solar cells (OSCs) performed power conversion efficiencies (PCEs) over 13%.The quantum efficiency losses in OSCs have been significantly reduced within the charge generation and extraction processes, resulting in high EQEPV (70-90%) and high FF (70-80%). Whereas, large voltage losses (Δ? = ??/? − ???) were observed in conventional fullerene based solar cells, and it has been the main limiting factor for further OPV advancement. Therefore, strategies to reduce the voltage losses are required.In this thesis, newly designed non-fullerene (NF) acceptors are used to construct novel material systems for high efficiency solar cells. In particular, we studied the hole transfer in these fullerene free systems. We also reported a NF system that exhibit ultrafast and efficient charge separation despite a negligible driving force, as ECT is nearly identical to ??. Moreover, the small driving force is found to have minimal detrimental effects on charge transfer dynamics of the OSCs. We demonstrate a NF based OSC with efficiency of 9.5% and internal quantum efficiency nearly 90% despite a low voltage loss of 0.61 V. This creates a path towards highly efficient OSCs with a low voltage loss.CT states in OSCs are also investigated, since VOC is governed by the CT energy (ECT), which is found as ???? = ??? − 0.6 in a large set of fullerene based solar cells. In order to reduce these recombination losses from CT states, we explored polymer-diPDI systems which exhibited weakened D-A coupling strength, due to the steric hindrance effect. The radiative recombination losses at D/A interface in these NF devices are all reduced to less than 0.18 eV. In particular, in some cases, the additional emission from pure material is favorable for suppressing the non-radiative CT states decay. Consequently, the recombination losses in these NF systems are reduced to 0.5 eV, while the charge generation is still efficient as confirmed by PL quenching and EQEPV.Novel material systems based on non-fullerene acceptors are investigated. The systems performed energy offsets (ΔHOMO or ΔLUMO) less than 0.15eV, resulting in the same energy of CT states and bulk excitons. In this regard, the charge transfer energy loss is minimized. We also found that the EL spectra as well as the EQEEL of the blend solar cells are similar with that of lower gap components in blends. Thus the non-radiative voltage losses are reduced to < 0.3V and small voltage loss of 0.5-0.7V are obtained. Meanwhile, the charge generation in systems are still efficient and high EQEPV of 50-70% can be achieved. It confirms that there is no intrinsic limit for the VOC and efficiency of OPVs as compared with other photovoltaic technologies.
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| 21. |
- Qin, Leiqiang, 1987-, et al.
(författare)
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Flexible Solid-State Asymmetric Supercapacitors with Enhanced Performance Enabled by Free-Standing MXene-Biopolymer Nanocomposites and Hierarchical Graphene-RuOx Paper Electrodes
- 2020
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Ingår i: Batteries & Supercaps. - : WILEY-V C H VERLAG GMBH. - 2566-6223. ; 3:7, s. 604-610
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Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional (2D) transition metal carbides and carbonitrides, called MXenes, with metallic conductivity and hydrophilic surfaces, show great promise as electrode materials for supercapacitors. A major drawback of 2D nanomaterials is the re-stacking of the nanosheets, which prevents full utilization of surface area and blocks the access of the electrolyte. In this study, a free-standing nanocomposite paper electrode is realized by combining Mo1.33C MXene and positively charged biopolymer lignin (the second most abundant biopolymer in nature, L-DEA). The self-assembled layered architecture with alternating polymer and MXene flakes increases the interlayer space to promote ion transport, and with combining charge storage capability of the lignin derivative and MXene in an interpenetrating MXene/L-DEA nanocomposite, which offers an impressive capacitance of 503.7 F g(-1). Moreover, we demonstrate flexible solid-state asymmetric supercapacitors (ASCs) using Mo1.33C@L-DEA as the negative electrode and electrochemically exfoliated graphene with ruthenium oxide (EG@RuOx) as the positive electrode. This asymmetric device operates at a voltage window of 1.35 V, which is about two times wider than that of a symmetric Mo1.33C@L-DEA based supercapacitor. Finally, the ASCs can deliver an energy density of 51.9 Wh kg(-1) at a power density of 338.5 W kg(-1), with 86 % capacitance retention after 10000 charge-discharge cycles.
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| 22. |
- Qin, Leiqiang, et al.
(författare)
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High-Performance Ultrathin Flexible Solid-State Supercapacitors Based on Solution Processable Mo1.33C MXene and PEDOT:PSS
- 2018
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 28:2
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Tidskriftsartikel (refereegranskat)abstract
- MXenes, a young family of 2D transition metal carbides/nitrides, show great potential in electrochemical energy storage applications. Herein, a high performance ultrathin flexible solid-state supercapacitor is demonstrated based on a Mo1.33C MXene with vacancy ordering in an aligned layer structure MXene/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) composite film posttreated with concentrated H2SO4. The flexible solid-state supercapacitor delivers a maximum capacitance of 568 F cm(-3), an ultrahigh energy density of 33.2 mWh cm(-3) and a power density of 19 470 mW cm(-3). The Mo1.33C MXene/PEDOT:PSS composite film shows a reduction in resistance upon H2SO4 treatment, a higher capacitance (1310 F cm(-3)) and improved rate capabilities than both pristine Mo1.33C MXene and the nontreated Mo1.33C/PEDOT:PSS composite films. The enhanced capacitance and stability are attributed to the synergistic effect of increased interlayer spacing between Mo1.33C MXene layers due to insertion of conductive PEDOT, and surface redox processes of the PEDOT and the MXene.
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| 23. |
- Qin, Leiqiang, 1987-, et al.
(författare)
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MXene-based multifunctional smart fibers for wearable and portable electronics
- 2022
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Ingår i: Journal of Materials Chemistry A. - : ROYAL SOC CHEMISTRY. - 2050-7488 .- 2050-7496. ; 10:23, s. 12544-12550
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Tidskriftsartikel (refereegranskat)abstract
- Fiber type devices are promising for applications in wearable and portable electronics. However, scalable fabrication of fiber electrodes with multifunctional performance for use in distinct fields remains challenging. Herein, high performance smart fibers based on Mo1.33C i-MXene nanosheets and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate hybrid paste are fabricated with an easily scalable spinning approach. The hybrid fibers produced by this method can be applied in both high-performance supercapacitors and electrochemical transistors (ECTs). When assembled into a fiber type asymmetric supercapacitor with reduced graphene oxide (rGO) fiber, a capacitance of 105 F g(-1) and an energy density of 37 mW h g(-1) were reached for a potential window of 1.6 V. The hybrid fiber based ECT shows high transconductance and fast response time. This work demonstrates the potential of i-MXene-based fiber electrodes for multifunctional applications, to aid in the development of the next-generation, high-performance wearable electronic devices.
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| 24. |
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| 25. |
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