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1.	Chen, Jun, et al. (författare) Effect of anti-icing coating functional groups on ice adhesion 2024 Ingår i: Applied materials today. - : Elsevier. - 2352-9407 .- 2352-9415. ; 39 Tidskriftsartikel (refereegranskat)abstract Unwanted ice build-up is a ubiquitous phenomenon in nature, which creates a series of catastrophic impacts on a wide range of human activities. Various anti/de-icing materials have been proposed for dealing with icing issues. Superhydrophobic anti/de-icing coatings have been widely reported since it has high efficiency and can be achieved in different ways. The surface functional groups have a significant influence on surface energy which is related to surface wettability. However, the influence of the coating surfaces functional groups on the anti-/de-icing properties is still not well studied. To investigate this influence, different groups with different hydrophilicity have been introduced to 3,3,4,4,5,5,6,6,7,7,8,8,8-Tridecafluorooctyl acrylate (TFOA) to fabricate several branch copolymer ice-phobic coatings. The anti-icing performance and the influence of group radius and interaction were studied. The acrylic acid TFOA showed a great superhydrophobic property (over 150° water contact angle), lower ice adhesion strength (<50 kPa), and lower wear depth compared with other copolymer coatings. The mechanism was studied via the molecular dynamic calculation carried out in ChemDraw software. The interaction between hydrophobic and hydrophilic groups and the steric length of the hydrophilic groups influence the surface structure and surface element distribution, further influencing the ice adhesion strength.
2.	Morales-Lopez, Alvaro, et al. (författare) Influence of surface characteristics of polypropylene on E. coli and S. aureus biofilms : From conventional to additive manufacturing of bioprocess equipment 2024 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407 .- 2352-9415. ; 39 Tidskriftsartikel (refereegranskat)abstract The fast-progressing landscape of the bioprocessing industry emphasizes innovation and efficiency enhancement, propelled by the integration of advanced solutions. Additive manufacturing technologies, particularly laserbased powder bed fusion with polypropylene, are pivotal in this industrial metamorphosis. However, despite the substantial scientific effort in the field, a significant gap exists in comprehending the surface characteristics of new surfaces and their implications for bacterial attachment and biofilm formation. This arises, in part, due to the absence of comprehensive and universally applicable topographical characterization analysis specifically designed for additively manufactured-fabricated surfaces. Typically, researchers tend to rely on the commonly used roughness parameter, Sa, that primarily quantifies the average height variation across a surface. Addressing this limitation is crucial for understanding the connection between surface characteristics and bacterial attachment dynamics. Here, we propose an innovative approach using surface analysis including confocal microscopy, advanced roughness measurements, and multivariate statistical analysis to uncover the connections between bacterial attachment for Gram negative Escherichia coli and Gram positive Staphylococcus aureus in early biofilm formation with surfaces produced by standardized and additively manufactured techniques. Finally, we advocate for the adoption of a set of roughness parameters that specifically describe the dale region of the surfaces. By doing so, we intend to establish direct links between surface texture and bacterial adhesion, thus contributing significantly to the advancement of both bioprocessing and additive manufacturing research domains.
3.	Atoufi, Zhaleh, et al. (författare) Synergistically stabilized wet foams from heat treated β-lactoglobulin and cellulose nanofibrils and their application for green foam production 2024 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 39 Tidskriftsartikel (refereegranskat)abstract Achieving a sustainable foam production requires a complete substitution of synthetic components with natural and renewable alternatives, as well as development of an environment-friendly production process. This work demonstrates a synergetic combination of heat-treated beta-lactoglobulin proteins and cellulose nanofibrils (CNFs) to create fully bio-based and highly-stable wet foams. Furthermore, a gradual reduction in the pH, enabled oven-drying of the wet foams without any major structural collapse of the foam, resulting in the preparation of lightweight solid foams with the density of 10.2 kg.m(-3). First, the foaming behavior of heat-treated beta-lactoglobulin systems (HBSs) containing amyloid nanofibrils (ANFs) and non-converted peptides was investigated at different pHs. Subsequently, the HBS foams were stabilized using CNFs, followed by a gradual acidification of the system to a final pH of 4.5. To gain a deeper understanding of the stabilization mechanism of the foam, the interactions between the foam's components, their positioning in the foam structure, and the viscoelasticity of the fibrillar network were investigated using quartz crystal microgravimetry, confocal microscopy and rheology. The analysis of the obtained data suggests that the stability of the foams was associated with the accumulation of CNFs and ANFs at the air-water interface, and that the concomitant formation of an intertwined network surrounding the air bubbles. This together resulted in a significant decrease in drainage rate of the liquid in the foam lamellae, bubble coarsening and bubble coalescence within the foams. The results also show that the major surface-active component participating in the creation of the foam is the free peptide left in solution after the formation of the ANFs. A slow reduction in pH to 4.5 lead to further gelation of the fibrillar network and an improved storage modulus of the foam lamellae. This resulted in a strong coherent structure that could withstand oven-drying without collapse. The density, porosity, microstructure and compressive mechanical properties of such prepared dry foams were assessed. Overall, the results demonstrate the potential of HBSs to replace synthetic surfactants and outlines a sustainable preparation protocol for the preparation of light-weight porous composite structures of ANFs and CNFs.
4.	Bollella, Paolo, et al. (författare) Cellobiose dehydrogenase : Insights on the nanostructuration of electrodes for improved development of biosensors and biofuel cells 2017 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 9, s. 319-332 Forskningsöversikt (refereegranskat)abstract Cellobiose dehydrogenase (CDH) is a versatile bioelectrocatalyst lately at focus due to its sugar oxidising properties in combination with its inherent ability for direct electron transfer communication with electrodes making it possible to be used in bioanodes in the enzymatic fuel cells (EFCs), self-powered biosensors, and biosupercapacitors. During the last 20 years, many new nanomaterials and hybrid nanocomposites have been developed and employed in combination with various oxidoreductases, such as CDH, to increase the overall performance of electrical devices (e.g. biosensors, EFCs etc.). It has also been shown that nanomaterials can be further chemically modified to facilitate electron transfer pathways between the biocomponent and electrodes. Both carbon and metal based nanomaterials and combinations thereof have been used together with CDH to improve the performance. In this review, we resume all the findings related to the influence of effective nanostructuration to improve the electron transfer communication with electrodes yielding higher sensitivity of biosensors or increasing the power output of EFC based on CDH from different sources.
5.	Curado, M. A., et al. (författare) Front passivation of Cu(In,Ga)Se-2 solar cells using Al2O3 : Culprits and benefits 2020 Ingår i: APPLIED MATERIALS TODAY. - : ELSEVIER. - 2352-9407. ; 21 Tidskriftsartikel (refereegranskat)abstract In the past years, the strategies used to break the Cu(In,Ga)Se-2 (CIGS) light to power conversion efficiency world record value were based on improvements of the absorber optoelectronic and crystalline properties, mainly using complex post-deposition treatments. To reach even higher efficiency values, further advances in the solar cell architecture are needed, in particular, with respect to the CIGS interfaces. In this study, we evaluate the structural, morphological and optoelectronic impact of an Al2O3 layer as a potential front passivation layer on the CIGS properties, as well as an Al2O3 tunneling layer between CIGS and CdS. Morphological and structural analyses reveal that the use of Al2O3 alone is not detrimental to CIGS, although it does not resist to the CdS chemical bath deposition. The CIGS optoelectronic properties degrade when the CdS is deposited on top of Al2O3. Nonetheless, when Al2O3 is used alone, the optoelectronic measurements reveal a positive impact of this inclusion such as a very low concentration of interface defects while keeping the same CIGS recombination channels. Thus, we suggest that an Al2O3 front passivation layer can be successfully used with alternative buffer layers. Depth-resolved microscopic analysis of the CIGS interface with slow-muons strongly suggests for the first time that low-energy muon spin spectroscopy (LE-mu SR) is sensitive to both charge carrier separation and bulk recombination in complex semiconductors. The demonstration that Al2O3 has the potential to be used as a front passivation layer is of significant importance, considering that Al2O3 has been widely studied as rear interface passivation material. (C) 2020 Published by Elsevier Ltd.
6.	Debbarma, Rousan, et al. (författare) Defect guided conduction in graphene-derivatives and MoS2 : Two-dimensional nanomaterial models 2021 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 23 Forskningsöversikt (refereegranskat)abstract The realization of unique scientific phenomena in two-dimensional nanomaterials (2DNMs) has led to their applications in several electronic fields; making it imperative to understand the conduction mechanism of charge carriers in such systems. Though several studies have been conducted on 2DNMs with pristine crystallinity, the inevitable presence of defects in the crystals requires careful consideration of their effect on 2DNMs’ electrical behavior. Here, we outline the effects of chemical, structural, substrate-induced defects and disorder on the conduction mechanism within 2DNMs, particularly graphene derivatives and MoS2. The conduction mechanisms discussed in this work are thermally activated conduction, nearest neighbor hopping, Efros-Shklovskii variable range hopping, and Mott variable range hopping. This review will be beneficial to the various material scientists studying the electronic properties of two-dimensional nanomaterials.
7.	Drozdz, Piotr A., et al. (författare) Highly efficient absorption of THz radiation using waveguide-integrated carbon nanotube/cellulose aerogels 2022 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier BV. - 2352-9407. ; 29 Tidskriftsartikel (refereegranskat)abstract This article presents the preparation, compositional and electromagnetic characterization of modified few-walled carbon nanotubes/nanofibrillar cellulose (FWCNT/NFC) aerogels integrated in a standard terahertz hollow waveguide and studies their operation as absorbers of electromagnetic waves in the WR-3.4 band (220-330 GHz). Hybrid aerogels consisting of different weight ratios of NFC and modified FWCNT are prepared by freezedrying and characterized through scanning electron microscopy and Raman spectroscopy, and then placed within waveguide cassettes in a simple, low-cost and efficient way that requires no special equipment. A broadband measurement setup is employed for examining the electromagnetic response of the materials. It is found that the materials are excellent absorbers with an average shielding efficiency of 66 dB in the best case and return loss above 10 dB across the band with a flat frequency response. FWCNT aerogels are assessed as a promising candidate for terahertz waveguide terminations.
8.	Du, Yong, et al. (författare) Flexible thermoelectric materials and devices 2018 Ingår i: APPLIED MATERIALS TODAY. - : ELSEVIER SCIENCE BV. - 2352-9407. ; 12, s. 366-388 Forskningsöversikt (refereegranskat)abstract Thermoelectric generators (TEGs) can directly convert waste heat into electrical power. In the last few decades, most research on thermoelectrics has focused on inorganic bulk thermoelectric materials and corresponding devices, and their thermoelectric properties have been significantly improved. An emerging topic is flexible devices, where the use of bulk inorganic materials is precluded by their inherent rigidity. The purpose of this paper is to review the research progress on flexible thermoelectric materials and generators, including theoretical principles for TEGs, conducting polymer TE materials, nanocomposites comprised of inorganic nanostructures in polymer matrices and fully inorganic flexible TE materials in nanostructured thin films. Approaches for flexible TEGs and components are reviewed, and remaining challenges discussed. (C) 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
9.	Erlandsson, Johan, et al. (författare) Macro- and mesoporous nanocellulose beads for use in energy storage devices 2016 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier. - 2352-9407. ; 5, s. 246-254 Tidskriftsartikel (refereegranskat)abstract Chemically cross-linked, wet-stable cellulose nanofibril (CNF) aerogel beads were fabricated using a novel procedure. The procedure facilitated controlled production of millimetre-sized CNF aerogel beads without freeze-drying or critical point drying, while still retaining a highly porous structure with low density. The aerogel beads were mechanically robust in the dry state, supporting loads of 1.3 N at 70% compression, even after being soaked in water and re-dried. Furthermore, they displayed both a good stability in water and a remarkably good shape recovery after wet compression. Owing to the stability in water, the entire surface of the highly porous aerogel beads could be successfully functionalized with polyelectrolytes and carboxyl-functionalized single-wall carbon nanotubes (CF-SWCNTs) using the Layer-by-Layer technique, introducing a significant electrical conductivity (1.6 mS/cm) to the aerogel beads. The functionalized, electrically conducting aerogel beads could carry as much as 2 kA/cm(2) and act as electrodes in a supercapacitor displaying a stabilized charge storage capacity of 9.8 F/g after 50 charging-discharging cycles.
10.	Fang, Yuan, et al. (författare) Quantifying lithium lost to plating and formation of the solid-electrolyte interphase in graphite and commercial battery components 2022 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 28 Tidskriftsartikel (refereegranskat)abstract A key degradation mechanism in lithium-ion batteries (LIBs) is the irreversible loss of cyclable lithium during cycling. At the graphite negative electrode, this loss occurs through the deposition of lithium-containing compounds in the solid-electrolyte interphase (SEI) and through plating of metallic lithium, resulting in so-called dead lithium. The separate quantification of SEI and dead lithium has so far been a challenge in post mortem analysis of commercial LIBs. Here we report a simple and fast 7Li nuclear magnetic resonance spectroscopy (NMR) protocol applied to solid-state samples derived from lab-built batteries to independently quantify these and other lithium species in graphite electrodes without the need for specialized cell design nor knowledge of prior charging history. The metallic lithium content is corroborated by electrochemical calculations; the total amount of lithium is also determined from 7Li liquid-state NMR and inductively coupled plasma optical emission spectroscopy (ICP-OES) in suitably digested samples. Factors influencing accuracy like the sample handling process, the radiofrequency skin effect, and re-intercalation losses are investigated. Measurements on samples from commercial cells aged under realistic conditions demonstrate quantification of dead lithium and remaining ionic species (SEI), and further reveal lithium dendrites entrained in the separator following cell disassembly. The method uses conventional and widely available NMR instrumentation and is applicable to samples from lab-scale test cells or commercial batteries, thereby presenting a vast improvement over prior post mortem methods.
11.	Fu, Le, et al. (författare) Biodegradable Si3N4 bioceramic sintered with Sr, Mg and Si for spinal fusion : Surface characterization and biological evaluation 2018 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 12, s. 260-275 Tidskriftsartikel (refereegranskat)abstract Silicon nitride (Si3N4) is an industrial ceramic used in spinal fusion and maxillofacial reconstructionbecause of its excellent mechanical properties and good biocompatibility. This study compares the sur-face properties, apatite formation ability, bacterial infection, cell-biomaterial interactions, and in vivotoxicity (zebrafish) of newly developed Si3N4 bioceramics (sintered with bioactive sintering additivesSrO, MgO and SiO2) with two standard biomaterials; titanium (Ti) and traditional Si3N4 bioceramics (sin-tered with standard sintering additives Al2O3 and Y2O3). In general, Si3N4 bioceramics (both the newlydeveloped and the traditional) displayed less in vitro bacterial affinity than Ti, which may arise fromdifferences in the surface properties between these two types of material. The newly developed Si3N4bioceramics developed lower biofilm coverage and thinner biofilm, compared to traditional Si3N4 bioce-ramics. The effects of ionic dissolution products (leach) on proliferation and differentiation of MC3T3-E1cell were also investigated. Ionic dissolution products containing moderate amount of Sr, Mg and Siions (approximately 4.72 mg/L, 3.26 mg/L and 3.67 mg/L, respectively) stimulated osteoblast prolifera-tion during the first 2 days in culture. Interestingly, ionic dissolution products from the traditional Si3N4bioceramics that contained small amount of Si and Y ions achieved the greatest stimulatory effect foralkaline phosphatase activity after 7 days culture. The toxicity of ionic dissolution products was investi-gated in a putative developmental biology model: zebrafish (Danio rerio). No toxicity, or developmentalabnormalities, was observed in zebrafish embryos exposed to ionic dissolution products, for up to 144 hpost fertilization. These newly developed Si3N4 bioceramics with bioactive sintering additives show greatpotential as orthopedic implants, for applications such as spinal fusion cages. Future work will focus onevaluation of the newly developed Si3N4 bioceramics using a large animal model.
12.	Geraldine Guex, Anne, et al. (författare) Controlling pH by electronic ion pumps to fight fibrosis 2021 Ingår i: Applied Materials Today. - : Elsevier. - 2352-9407. ; 22 Tidskriftsartikel (refereegranskat)abstract Fibrosis and scar formation is a medical condition observed under various circumstances, ranging from skin wound healing to cardiac deterioration after myocardial infarction. Among other complex interdependent phases during wound healing, fibrosis is associated with an increased fibroblast to myofibroblast transition. A common hypothesis is that decreasing the pH of non-healing, alkaline wounds to a pH range of 6.0 to 6.5 increases healing rates. A new material-based strategy to change the pH by use of electronic ion pumps is here proposed. In contrast to passive acidic wound dressings limited by non-controlled delivery kinetics, the unique electronic ion pump design and operation enables a continuous regulation of pH by H+ delivery over prolonged durations. In an in vitro model, fibroblast to myofibroblast differentiation is attenuated by lowering the physiological pH to an acidic regime of 6.62 +/- 0.06. Compared to differentiated myofibroblasts in media at pH 7.4, gene and protein expression of fibrosis relevant markers alpha-smooth muscle actin and collagen 1 is significantly reduced. In conclusion, myofibroblast differentiation can be steered by controlling the pH of the cellular microenvironment by use of the electronic ion pump technology as new bioelectronic drug delivery devices. This technology opens up new therapeutic avenues to induce scar-free wound healing. (C) 2021 The Authors. Published by Elsevier Ltd.
13.	Ghanadpour, Maryam, 1984-, et al. (författare) Ultrastrong and flame-resistant freestanding films from nanocelluloses, self-assembled using a layer-by-layer approach 2017 Ingår i: Applied Materials Today. - : Elsevier. - 2352-9407. ; 9, s. 229-239 Tidskriftsartikel (refereegranskat)abstract Nanosized cellulose nanofibrils (CNF) prepared from phosphorylated pulp fibers (P-CNF) are combined with CNF prepared from aminated fibers (cationic CNF) through a layer-by-layer (LbL) assembly to prepare a freestanding, transparent all-cellulose film. It is shown that the thermal stability and flame-retardant properties of the all CNF film are significantly improved when phosphorylated CNF is combined with cationic fibrils in an LbL assembled structure. The freestanding films also show a tensile strength of 160 MPa and a Young's modulus of 9 GPa, placing it among strongest freestanding LbL films fabricated so far, showing large promise for the use of these types of ultrathin films in advanced applications. The LbL build-up of the cationic CNF/P-CNF multilayer film is carefully studied by quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). Hydrophobized silicon substrates are used for the LbL deposition and it is shown that the (cationic CNFIP-CNF)(300) film, 2.3 pin thick, can be easily detached from the substrate using tweezers. The thermal stability, combustion behavior and mechanical properties of the films are further studied by thermogravimetric analysis, combustion and tensile tests respectively.
14.	Gong, Jiang, et al. (författare) Cooking carbon in a solid salt : Synthesis of porous heteroatom-doped carbon foams for enhanced organic pollutant degradation under visible light 2018 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 12, s. 168-176 Tidskriftsartikel (refereegranskat)abstract Porous heteroatom-doped carbons are desirable for catalytic reactions due to their tunable physicochemical properties, low cost and metal-free nature. Herein, we introduce a facile, general bottom-up strategy, so-called cooking carbon in a solid salt, to prepare hierarchically porous heteroatom-doped carbon foams by using poly(ionic liquid) as precursor and a common inorganic salt as structural template. The obtained carbon foams bear hierarchical micro-/meso-/macropores, large specific surface area and rich nitrogen dopant. The combination of these favorable features facilitates the catalytic degradation of aqueous organic pollutants by persulfate under visible light irradiation, in which they prevail over the state-of-the-art metal-/carbon-based catalysts.
15.	Goulas, Athanasios, et al. (författare) Assessing extraterrestrial regolith material simulants for in-situ resource utilisation based 3D printing 2017 Ingår i: Applied Materials Today. - Amsterdam : Elsevier. - 2352-9407. ; 6, s. 54-61 Tidskriftsartikel (refereegranskat)abstract This research paper investigates the suitability of ceramic multi-component materials, which are found on the Martian and Lunar surfaces, for 3D printing (aka Additive Manufacturing) of solid structures. 3D printing is a promising solution as part of the cutting edge field of future in situ space manufacturing applications.3D printing of physical assets from simulated Martian and Lunar regolith was successfully performed during this work by utilising laser-based powder bed fusion equipment. Extensive evaluation of the raw regolith simulants was conducted via Optical and Electron Microscopy(SEM), Visible–Near Infrared/Infrared (Vis–NIR/IR) Spectroscopy and thermal characterisation via Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The analysis results led to the characterisation of key properties of these multi-component ceramic materials with regard to their processability via powder bed fusion 3D printing.The Lunar and Martian simulant regolith analogues demonstrated spectral absorbance values of up to 92% within the Vis–NIR spectra. Thermal analysis demonstrated that these materials respond very differently to laser processing, with a high volatility (30% weight change) for the Martian analogue as opposed to its less volatile Lunar counterpart (<1% weight change). Results also showed a range of multiple thermal occurrences associated with melting, glass transition and crystallisation reactions. The morphological features of the powder particles are identified as contributing to densification limitations for powder bed fusion processing.This investigation has shown that – provided that the simulants are good matches for the actual regoliths – the lunar material is a viable candidate material for powder bed fusion 3D printing, whereas Martian regolith is not. © 2016 Elsevier Ltd
16.	He, Jianqiao, et al. (författare) Ferrocene-integrated conjugated microporous polymer nanosheets : Active and regenerative catalysts for photomediated controlled radical polymerization 2020 Ingår i: Applied materials today. - : Elsevier BV. - 2352-9407. ; 18 Tidskriftsartikel (refereegranskat)abstract The challenge of light-driven controlled radical polymerization through non-noble metal catalyst remains the most significant issue. Ferrocene-bearing microporous aromatic polymer nanosheets (termed FeMAP-11) that feature high chemical stability were reported here to synergistically combine the advantageous properties of the redox-active ferrocene units and the conjugated microporous polymers (CMPs), and to be able to serve as photocatalyst for activators regenerated by electron transfer atom transfer radical polymerization (AGET-ATRP). It succeeded in initiating polymerizations of 3 common vinyl monomers, i.e. methyl methacrylate (MMA), methacrylate (MA) and styrene (St), and produced polymers with controlled molecular weight and relatively low molecular weight dispersity ((1) over tilde .3). Benefiting from steric hindrance through ketone-amine chemistry, the microporous catalyst with tolerance to acidic and basic media was found stable under the AGET-ATRP conditions. It showed negligible metal leaching and good recyclability for at least 10 cycles without sacrifice of its catalytic performance. Our tests proved that FeMAP-11 exceeded the state-of-the-art ATRP photocatalysts such as UiO-66-NH2, titanium MOF-901 and the commercial P-25 Titania, demonstrating promising potential in catalysis in view of green chemistry.
17.	Holmstrom, Erik, et al. (författare) High entropy alloys : Substituting for cobalt in cutting edge technology 2018 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier BV. - 2352-9407. ; 12, s. 322-329 Tidskriftsartikel (refereegranskat)abstract Cemented carbide, also known as hard metal, is one of the most outstanding composite engineering materials since its commercial introduction in the 1920s. The unique combination of strength, hardness and toughness makes cemented carbides highly versatile materials for the most demanding engineering applications. In their simplest form, these materials are composites of tungsten carbide (WC) grains that are cemented with a ductile metallic binder phase, typically cobalt. However, despite the superiority of Co as binder material, there is a long-standing need to find alternative binders due to serious health concerns that have haunted the industry for nearly 80 years. In the present study, we develop a new cemented carbide with a high entropy alloy binder phase (CoCrFeNi) from raw materials to a fully functional, coated and gradient-sintered cutting tool insert. The new hard metal with reduced Co content is designed by using first principles theory and the CALPHAD method. The cutting tool was made by pressing the new hard metal in a standard geometry, sintered to have a thin binder phase enriched surface zone, free from cubic carbides and coated with protective layers of Ti(C,N) and Al2O3. The resulting cutting insert was tested in a real machining operation and compared to a state-of-the-art reference that had Co as binder phase. The cutting tool made of the newly developed cemented carbide has an exceptionally high resistance against plastic deformation at all tested cutting speeds in the machining test, outperforming the reference insert, which shows a linear increase in edge depression when the cutting speed is increased. This result opens up the possibility to utilize the unique properties of high entropy alloys for industrial applications, in particular, as binder phase in new cemented carbides.
18.	Jain, Karishma, et al. (författare) 3D printable composites of modified cellulose fibers and conductive polymers and their use in wearable electronics 2023 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier BV. - 2352-9407. ; 30 Tidskriftsartikel (refereegranskat)abstract There are many bioelectronic applications where the additive manufacturing of conductive polymers may be of use. This method is cheap, versatile and allows fine control over the design of wearable electronic devices. Nanocellulose has been widely used as a rheology modifier in bio-based inks that are used to print electrical components and devices. However, the preparation of nanocellulose is energy and time consuming. In this work an easy-to-prepare, 3D-printable, conductive bio-ink; based on modified cellulose fibers and poly(3,4-ethylene dioxythiophene) poly(styrene sulfonate) (PEDOT:PSS), is presented. The ink shows excellent printability, the printed samples are wet stable and show excellent electrical and electrochemical performance. The printed structures have a conductivity of 30 S/cm, high tensile strains (>40%), and specific capacitances of 211 F/g; even though the PEDOT:PSS only accounts for 40 wt% of the total ink composition. Scanning electron microscopy (SEM), wide-angle X-ray scattering (WAXS), and Raman spectroscopy data show that the modified cellulose fibers induce conformational changes and phase separation in PEDOT:PSS. It is also demonstrated that wearable supercapacitors and biopotential-monitoring devices can be prepared using this ink.
19.	Kaline P., Furlan (författare) Photonic materials for high-temperature applications: Synthesis and characterization by X-ray ptychographic tomography 2018 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 13, s. 359-369 Tidskriftsartikel (refereegranskat)abstract Photonic materials for high-temperature applications need to withstand temperatures usually higher than 1000 °C, whilst keeping their function. When exposed to high temperatures, such nanostructured materials are prone to detrimental morphological changes, however the structure evolution pathway of photonic materials and its correlation with the loss of material's function is not yet fully understood. Here we use high-resolution ptychographic X-ray computed tomography (PXCT) and scanning electron microscopy (SEM) to investigate the structural changes in mullite inverse opal photonic crystals produced by a very-low-temperature (95 °C) atomic layer deposition (ALD) super-cycle process. The 3D structural changes caused by the high-temperature exposure were quantified and associated with the distinct structural features of the ceramic photonic crystals. Other than observed in photonic crystals produced via powder colloidal suspensions or sol-gel infiltration, at high temperatures of 1400 °C we detected a mass transport direction from the nano pores to the shells. We relate these different structure evolution pathways to the presence of hollow vertexes in our ALD-based inverse opal photonic crystals. Although the periodically ordered structure is distorted after sintering, the mullite inverse opal photonic crystal presents a photonic stopgap even after heat treatment at 1400 °C for 100 h.
20.	Li, Tianzhong, et al. (författare) Material-based engineering of bacteria for cancer diagnosis and therapy 2021 Ingår i: Applied Materials Today. - : Elsevier. - 2352-9407. ; 25 Tidskriftsartikel (refereegranskat)abstract Various categories of biomaterials have been utilized for drug delivery, genetic modification, photodynamic and photothermal therapies due to their distinct physicochemical properties, including photothermal convertibility, stimuli-responsiveness, and inherent capability to generate photodynamical radicals. However, successful treatments of cancer are largely hindered by the limited accessibility of nanomaterials into hypoxic or metastatic tumor tissues. Among the various tumor-targeting strategies, bacterial fabrication exhibits particular advantages such as specific hypoxia tropism, high motility, and rapid self replication. Biomineralization, i.e. bacterial modification, involves the fabrication of bacteria by nanomaterials for precise cancer imaging as well as targeted drug delivery, overcoming the physiological barriers and improving the therapeutic efficiency. Fabrication of bacteria strains can be conducted by various methods, including direct adsorption, electrostatic interaction, covalent ligation, and surface precipitation. In this review, a brief introduction to commonly-utilized biomaterials and bacteria species is provided. A systemic overview of recent advances of bacteria fabrication strategies and techniques are then discussed, followed by future prospective of bacteria-facilitated cancer therapy and diagnostics.
21.	Luo, GH, et al. (författare) Recent progresses on radiotherapeutics-based treatment of cancer with two-dimensional nanomaterials 2022 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier BV. - 2352-9407. ; 29 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
22.	Majumdar, Arnab, et al. (författare) Pressure induced structural phase transition and piezochromism in photovoltaic sillen compounds PbBiO2X (X = Cl, Br & I) 2022 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier. - 2352-9407. ; 26 Tidskriftsartikel (refereegranskat)abstract Hydrostatic pressure is an effective and clean method that can give rise to the emergence of novel crystal structures and physical properties. Thus, hydrostatic pressure can be used for designing new functional materials. Sillen materials or PbBiO2X (X = Cl, Br & I) are a class of materials which have gained considerable interest in the field of ferroelectrics, photocatalysis, etc . In this work, we have used first principles methods to predict the crystal structure and phase of sillen materials at different pressure points from 0 to 50 GPa. It was then followed by the study of their structural, electronic and optical properties upon compression. Upon compression, the band gaps decreased within a particular phase and showed kinks on phase transitions. In the compressed states, the band gaps are in the suitable range to be used in the visible range of the spectrum for photovoltaic properties. Piezochromism is also reported upon compression as can been seen from the changes in the optical absorption spectra. This work should remove any confusion with regards to the responsible phase at different pressures, and the possible existence of new phases with the respective band gaps should pave the way for future experimental works on photocatalysis and other energy applications. (c) 2022 The Author(s). Published by Elsevier Ltd.& nbsp;
23.	Markstedt, Kajsa, 1989, et al. (författare) Materials from trees assembled by 3D printing – Wood tissue beyond nature limits 2019 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 15, s. 280-285 Tidskriftsartikel (refereegranskat)abstract Materials from trees have the potential to replace fossil based and other non-sustainable materials in everyday products, thus transforming the society back to a bioeconomy. This paper presents a 3D printing platform which mimics wood biogenesis for the assembly of wood biopolymers into wood-like hierarchical composites. The genome was substituted with G-code, the programming language which controls how the 3D printer assembles material. The rosette was replaced by the printer head for extrusion of cellulose. Instead of microtubules guiding the alignment of cellulose, the printing direction was guided by an x/y stage, thus mimicking the microfibril angle. The printed structures were locked by an enzymatic crosslinking reaction similar to what occurs in the cell wall upon lignification. Hierarchical structures characteristic for wood were designed and printed with control of density, swelling and directional strength. Accelerating the development of the 3D printing technology helps realize the circular bioeconomy where garments, packaging, furniture and entire houses are manufactured by 3D printing wood.
24.	Naqvi, Syeda Rabab, et al. (författare) Exploring two-dimensional M2NS2 (M = Ti, V) MXenes based gas sensors for air pollutants 2020 Ingår i: Applied Materials Today. - : Elsevier. - 2352-9407. ; 19 Tidskriftsartikel (refereegranskat)abstract Albeit a very recent development, Mxenes have offered numerous potential avenues for researchers from physics, chemistry and materials science. Here in, we have explored S-terminated M2N (M = Ti, V) MXenes, which are one of the lightest and thinnest members of the MXene family, for gas sensing applications. We performed spin-polarized DFT calculations with vdW correction to investigate the sensing propensity of several gases such as CH4, CO, CO2, NH3, NO, NO2, H2S, and SO2 on M2NS2 sheets. The adsorption kinetics, charge transfer, electronic density of states (DOS) and electronic transport behaviors are investigated in relation to M2NS2 Mxene based nanoscale gas sensor. Among all the gases under consideration, NO, and NO2 exhibit superior sensitivity towards 2D nitride MXenes. Charge transfer analysis reveals that the considerable quantity of charge is transferred from NO, and NO2 gas molecules to Ti2NS2 and V2NS2 MXene sheets, respectively. Spin-polarized DOS reveals that pristine non-magnetic nitride Mxenes transform to magnetic systems upon NO and NO2 adsorption. By computing the electronic transport properties in the form of I–V characteristics for adsorbed gases on M2NS2 and comparing it against the pristine Mxene sheets, distinct changes in I–V relationships can be identified which further substantiate the promising role of Mxenes for gas sensing applications.
25.	Ni, Bin, et al. (författare) Linear contracting and air-stable electrochemical artificial muscles based on commercially available CNT yarns and ionically selective ionogel coatings 2023 Ingår i: APPLIED MATERIALS TODAY. - : ELSEVIER. - 2352-9407. ; 31 Tidskriftsartikel (refereegranskat)abstract Artificial muscles, or soft actuators, that could exhibit contractile stroke and operate in open-air, would be crucial for many applications, such as robotics, prosthetics, or powered exoskeletons. Amongst the different artificial muscle technologies, electrochemical carbon nanotube (CNT) yarn muscles, transducing capacitively ionic accumulation at the electrochemical double layer into linear contraction, are amongst the most promising candidates. However, their performances are either limited by an undesired bipolar behaviour or short lifetime due to the inevitable drying of water-based electrolytes. In this paper, we present here the fabrication of air -operating contractile linear artificial muscles from commercially available CNT yarns exhibiting outstanding performance. The synthesis and the junction of two ionogels based on cationic and anionic polyelectrolyte have been designed for the coating process on CNT yarns, and for selectively orienting the ionic flow allowing optimal electromechanical energy conversion. The dual-electrode CNT yarn actuators showed air-stable unipolar con-tractile stroke, reaching 9.7% without loss of performances after 2000 cycles.
26.	Parakhonskiy, Bogdan, V, et al. (författare) A method of drug delivery to tumors based on rapidly biodegradable drug-loaded containers 2021 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier. - 2352-9407. ; 25 Tidskriftsartikel (refereegranskat)abstract To mitigate side effects in systemic administration, anticancer drugs are encapuslated in nanocontainers. The nanocontainers are impermeable through normal vessel walls but can permeate and retain in the tumor, albeit their diffusive transport in the tumor interstitium towards pharmacological targets is drastically hindered by the tumor microenvironment resulting in a compromised therapeutic efficacy. We introduce a new drug delivery concept, which relies on drug container passive accumulation in the tumor vasculature followed by an hours-scale release of small-molecule payload that cross the capillary walls to the tumor interstitium and permeates the tumor parenchyma. To demonstrate this approach, a colloidal solution of geology-inspired sub-micron vaterite particles (VPs) loaded with photosensitiser drug porphyrazine was used to deliver and visualise porphyrazine biodistribution in the tumors in vivo . The tumor uptake of polyethylene-glycol-coated gold nanorods and porphyrazine was enhanced c.a 4-fold and 1.8-fold, respectively, when formulated in VP containers. The tumor uptake of similar to 30%ID/g much higher than the field average was achieved and enabled successful photodynamic therapy.
27.	Ranjan, Alok, 1992, et al. (författare) Probing resistive switching in HfO 2 /Al 2 O 3 bilayer oxides using in-situ transmission electron microscopy 2023 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 31 Tidskriftsartikel (refereegranskat)abstract In this work, we investigate the resistive switching in hafnium dioxide (HfO2) and aluminum oxide (Al2O3) bilayered stacks using in-situ transmission electron microscopy and X-ray energy dispersive spectroscopy. Conductance of the HfO2/Al2O3 stack changes gradually upon electrical stressing which is related to the formation of extended nanoscale physical defects at the HfO2/Al2O3 interface and the migration and re-crystallization of Al into the oxide bulk. The results suggest two competing physical mechanisms including the redistribution of oxygen ions and the migration of Al species from the Al electrode during the switching process. While the HfO2/Al2O3 bilayered stack appears to be a good candidate for RRAM technology, the low diffusion barrier of the active Al electrode causes severe Al migration in the bi-layered oxides leading to the device to fail in resetting, and thereby, largely limiting the overall switching performance and material reliability.
28.	Saeedi Garakani, Sadaf, 1993-, et al. (författare) Poly(ionic liquid)-derived metal-free heteroatom co-doped porous carbons with peroxidase-like activity Ingår i: Applied materials today. - 2352-9407. Tidskriftsartikel (refereegranskat)abstract Development of affordable, efficacious and metal-free heterogeneous catalytic systems has been a persistent challenge in academia and industry. Heteroatom-doped metal-free carbon materials are increasingly recognized as valuable heterogeneous catalysts, and if well-designed, can present comparable performance to, or even surpass transition metal-containing catalysts. Their physicochemical properties and structural characteristics are tunable in a wide range, plus being free of leakage of transition metal species into the environment. Herein, three types of hierarchically porous N/X co-doped carbon materials (X denotes B, P or S) were synthesized via using poly(ionic liquid)s (PILs) as carbon precursors and source of heteroatom dopants. The incorporation of sacrificial pore-inducing templating agents which created abundant edge defects, in combination with a heteroatom co-doping strategy enhanced the number of active sites and their peroxidase-like catalytic activities. Comparison with only nitrogen single-doped porous carbons as reference demonstrated that co-doping with nitrogen and another heteroatom exhibits higher peroxidase-like activity and affinity towards substrates. Among the three types of heteroatom co-doped porous carbonaceous artificial enzymes, the N/B co-doped carbonaceous catalyst displayed the highest specific activities and Vmax values. These observations suggest a synergistic effect of the co-dopants, here N and B in the enzyme that holds a promising potential to further enhance peroxidase-like activity.
29.	Saeedi Garakani, Sadaf, 1993-, et al. (författare) Poly(ionic liquid)-derived metal-free heteroatom co-doped porous carbons with peroxidase-like activity 2024 Ingår i: Applied Materials Today. - 2352-9407. ; 37 Tidskriftsartikel (refereegranskat)abstract Development of affordable, efficient and metal-free heterogeneous catalytic systems has been a persistent challenge in academia and industry. Heteroatom-doped metal-free carbon materials are increasingly recognized as valuable heterogeneous catalysts, and if well-designed, can present comparable performance to, or even surpass transition metal-containing catalysts. Their physicochemical properties and structural characteristics are tunable in a wide range, plus being free of leakage problems of transition metal species into the environment. Herein, three types of hierarchically porous N/X co-doped carbon materials (X denotes B, P or S) were synthesized via using poly(ionic liquid)s (PILs) as carbon precursors and source of heteroatom dopants. The incorporation of sacrificial pore-inducing templating agents which created abundant edge defects, in combination with a heteroatom co-doping strategy, enhanced the number of active sites and their peroxidase-like catalytic activities. Comparison with only nitrogen single-doped porous carbons as reference demonstrated that co-doping with nitrogen and another heteroatom exhibits higher peroxidase-like activity and affinity towards substrates. Among the three types of heteroatom co-doped porous carbonaceous artificial enzymes, the N/B co-doped carbonaceous catalyst displayed the highest specific activities and Vmax values. These observations suggest a synergistic effect of the co-dopants, here N and B in the enzyme that holds a promising potential to further enhance peroxidase-like activity.
30.	Sanati, Alireza, et al. (författare) Recent advancement in electrode materials and fabrication, microfluidic designs, and self-powered systems for wearable non-invasive electrochemical glucose monitoring 2022 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 26, s. 101350- Tidskriftsartikel (refereegranskat)abstract Due to the ever-increasing number of diabetic people globally, continuous monitoring of glucose became an increasingly important subject in the field of point-of-care diagnosis. However, there are still many shortcomings of current diagnostic approaches, including materials and device design, comfort, and stability of device performance. Here, brief, albeit comprehensive, information on current trends of using novel materials and techniques to fabricate wearable electrochemical biosensors for continuous and non-invasive glucose monitoring are provided. Flexible materials as versatile substances to fabricate wearable glucose biosensors used in various body fluids, including sweat, interstitial body fluid (ISF), saliva, and tear, are studied. Moreover, current electrode fabrication methods such as printing, laser induction, photolithography, electrodeposition, seed mediation, and dealloying to construct porous and one-dimensional material with interesting mechanical properties are explored. Microfluidic designs and self-powered systems for better control and storage of the body fluids and decreasing the weight, size, and cost of the wearable electrochemical glucose devices are also studied in this review. The overall progress made to date in building such conceptualized efforts for real-time, wearable continuous monitoring of glucose and the future of the field is briefly discussed. This review has benefits compared to previous reviews, as recent developments in continuous glucose monitoring have interestingly combined with two other amazing and innovative subjects of biosensing, including microfluidics and self-powered systems.
31.	Shyam, Priyank, et al. (författare) Sintering in seconds, elucidated by millisecond in situ diffraction 2023 Ingår i: Applied Materials Today. - 2352-9407. ; 35 Tidskriftsartikel (refereegranskat)abstract Materials, when sintered at high temperatures, undergo structural changes on multiple, hierarchical length scales but getting realtime information on these changes is difficult. To address this challenge, we developed a custom-built sample environment that allows us to investigate the structural evolution of materials during sintering using high-energy two-dimensional synchrotron X-ray diffraction (2D-XRD). Changes in the structure of SrFe12O19 ceramic magnet at multiple length scales were tracked in situ and modelled with millisecond time-resolution. In addition, we also demonstrated the ability to perform quantitative texture analysis from individual 2D-XRD images with a time resolution of 4 ms each. Owing to the high brightness X-ray source and advanced X-ray detectors, the evolution of crystallographic texture could be followed during sintering. This in situ approach can aid understanding of the synthesis–structure–property relationships in sintered materials, enabling the development of improved functional materials.
32.	Sun, Xiaoming, et al. (författare) Adjustable hardness of hydrogel for promoting vascularization and maintaining sternness of stem cells in skin flap regeneration 2018 Ingår i: Applied Materials Today. - : Elsevier. - 2352-9407. ; 13, s. 54-63 Tidskriftsartikel (refereegranskat)abstract The matrix mechanical stiffness of biomaterials plays an important role in the pluripotency and biological function of stem cells in the microenvironment. It is a key step to adjust the stiffness of biomaterials for inducing stem cells to promote vascularization in order to promote damaged tissue repair. In this study, we transplant adipose derived stem cells (ADSCs) within an in situ forming dextran hydrogel with controllable mechanical strength formed by cross-linking glycidyl methacrylate derivatized dextran and dithiothreitol, which can regulate the stemness and biological functions of stem cells. We show that softer dextran hydrogel can better maintain stemness markers expression of ADSCs, and significantly stimulate ADSCs to secrete angiogenic factors. The ADSCs-encapsulated hydrogel distinctly promote the skin flap survival compared to direct cell injection. Bioluminescence imaging analysis shows that in situ forming dextran hydrogel can improve cells retention, and postmortem analysis reveals that the transplanted ADSCs with hydrogel can promote vascularization. These results support the use of injectable dextran hydrogel for skin ischemia tissue regeneration. (C) 2018 Elsevier Ltd. All rights reserved.
33.	Sun, X, et al. (författare) Tracking stem cells and macrophages with gold and iron oxide nanoparticles - The choice of the best suited particles 2019 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier BV. - 2352-9407. ; 15, s. 267-279 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
34.	Tomer, Vijay K., et al. (författare) Superior visible light photocatalysis and low-operating temperature VOCs sensor using cubic Ag(0)-MoS2 loaded g-CN 3D porous hybrid 2019 Ingår i: APPLIED MATERIALS TODAY. - : ELSEVIER. - 2352-9407. ; 16, s. 193-203 Tidskriftsartikel (refereegranskat)abstract Two-dimensional materials are incipient as an innovative class of multifunctional elements with promising attributes for energy and environmental applications. Herein, a novel nanohybrid consisting of Ag-MoS2 loaded mesoporous g-C3N4 (herein 'm-CN') with ordered structure was synthesized by a nanocasting method using cubic and ordered mesoporous silica (KIT-6) as a hard template. Due to its unique 3D mesoporous architecture, the as-synthesized Ag-MoS2 @m-CN nanohybrid revealed excellent visible-light absorption for enhanced charge separation of photo-induced e(-)-h(+) pairs to improve the degradation performance, high stability, and reusability with respect to Rhodamine B (RhB). The measured very high degradation efficiency is explained by synergistic effects from catalytically active Ag and MoS2 nanoparticles cumulatively decorated on the cubic mesoporous m-CN in form 3D mesoporous architecture. Additionally, the Ag-MoS2@m-CN nanohybrid exhibits high response and selectivity toward n-butanol gas at low-operating temperatures for reliable detection of volatile organic compounds (VOCs). The photocatalysis behavior and VOC sensing response of Ag-MoS2@m-CN nanohybrid material are discussed in detail for possible various application avenues toward environmental purifications and monitoring. (C) 2019 Elsevier Ltd. All rights reserved.
35.	Wang, Wei, 1995-, et al. (författare) Mesoporous Ni-N-C as an efficient electrocatalyst for reduction of CO2 into CO in a flow cell 2022 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 29 Tidskriftsartikel (refereegranskat)abstract Recently, nitrogen-doped porous carbon materials containing non-precious metals (termed “M-N-C”) have formed a group of functional materials to replace precious metal-based catalysts for electrochemical CO2 reduction reaction. Here, a series of mesoporous Ni-N-C electrocatalysts (termed “mp-Ni-N-Cs”) were prepared via a gel-template method, and could effectively reduce CO2 into CO in a flow cell. The result in gas sorption tests exhibited a typical mesoporous structure, which would bring both sufficient exposed active sites and convenient mass transfer channels. Electrochemical tests showed excellent performance at an applied potential of -1.3 V (vs. RHE), e.g., a CO Faradaic efficiency (FECO) of 95.85 %, and a CO reduction current (jCO) of -21.29 mA cm−2. Significantly, its FECO exceeded 93 % in a wide range of potentials from -1.0 to -1.5 V, showing great tolerance to fluctuation in potential. The mp-Ni-N-C electrocatalysts have satisfactory features in terms of catalytic activity, facile preparation, and economic feasibility, and will offer a valuable reference for next exploration of cost-effective electrocatalysts for CO2 conversion.
36.	Wei, Zhu, et al. (författare) Injectable and assembled 3D solid structure for free-to-fixed shape in bone reconstruction 2020 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 21 Tidskriftsartikel (refereegranskat)abstract There is a gap between injectable and scaffold-like bioceramics. Injectable bioactive materials, such as bone cement and hydrogel, are good for minimized surgery, but the extremely low porosity and small pore size limited enhanced bone repair and regeneration. Macroporous bioceramic scaffolds are used because of the controlled pore size and porosity, but not injectable. It's a challenge of preparation of an injectable macroporous ceramic scaffold for minimized bone reconstruction. By using the reversible setting reaction of calcium sulfate and combining a dual setting system with magnesium silicate hydrate, the injectable and assembled 3D porous bioceramic scaffold has been successfully developed. The content of amorphous magnesium silicate hydrate in the dual setting system affected the mechanical strength and degradation. The porous structure could be controlled by the size of granules. The granules can also be used for the fabrication of porous materials with varied shapes and customized structures by using a simple injection process. The biological testing showed good biocompatibility and in vitro osteogenesis. By using the femoral lateral condyle defect model, we can see the granules could be injected into the defect and formed a rigid porous structure in situ, and further presented better new bone formation compared with autologous bone chips. Briefly, we demonstrated the first injectable 3D solid porous ceramic structure for minimized bone repair and free-form shaping.
37.	Xenidis, Nikolaos, et al. (författare) Dichroic absorption of aligned graphene-augmented inorganic nanofibers in the terahertz regime 2024 Ingår i: Applied Materials Today. - : Elsevier BV. - 2352-9407. ; 39 Tidskriftsartikel (refereegranskat)abstract This article investigates the dichroic properties of aligned γ-Al2O3 nanofibers coated with graphene in the terahertz (THz) regime, revealing significant variance in absorption based on the orientation of the electric field in relation to the nanofibers, arising from the anisotropic nature of the material. Samples are prepared in a hot-wall chemical vapor deposition reactor with varying growth times, resulting in 5 samples with increasing graphene content. Compositional characterization is carried out using scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy. The samples are characterized electromagnetically using two distinct measurement techniques. First, a novel waveguide measurement setup is deployed, wherein square waveguide cassettes are used to capture the anisotropic behavior of the material and equally measure both polarization states in 67–500 GHz. Then, the samples are characterized using terahertz time-domain spectroscopy up to 4 THz. Both techniques highlight absorption enhancement when the electric field is parallel to the fibers, opening new possibilities for THz devices using polarization filtering.
38.	Zhao, Xue, et al. (författare) Two-dimensional BCN matrix inlaid with single-atom-Cu driven electrochemical nitrate reduction reaction to achieve sustainable industrial-grade production of ammonia 2021 Ingår i: APPLIED MATERIALS TODAY. - : Elsevier. - 2352-9407. ; 25 Tidskriftsartikel (refereegranskat)abstract Electrochemical methods have been proven to effectively eliminate nitrates in sewage and convert them into high value-added ammonia products. Here, after annealing treatment of metal boron cluster organic polymers formed by the combination of 1,10-phenanthroline, Cu2+ and closo-[B12H12](2)(-), a Cu single-atom doped BCN (B-doped CN) with a diamond-shaped nanosheet structure was obtained. In the electrochem-ical reduction reaction of nitrate, BCN-Cu exhibits excellent catalytic activity, specifically: 1) the ammonia yield rate reached as high as 498.85 mu g h(-1) cm(-2), 1047.14 mu g h(-1) cm(-2), 1900.07 mu g h(-1) cm(-2) and 3358.74 mu g h(-1) cm(-2) at -0.3 V, -0.4 V, -0.5 V and -0.6 V vs reversible hydrogen electrode, respectively, and Faradaic efficiency is 95.90%, 97.28%, 98.23% and 97.37%; 2) after repeated use of BCN-Cu 10 times or continuous operation for 16 h, the activity against electrochemical reduction reaction of nitrate anions is almost unchanged. The (NO3-)-N-15 isotopic labeling experiment proved that the detected NH3 comes from the reduction of NO3- on BCN-Cu. Control experiments show that the presence of Cu determines whether BCN-Cu has the possibility of catalyzing electrochemical reduction reactions of nitrate, and the presence of the B element enhances the catalytic activity of BCN-Cu. Density functional calculations indicate that in the water phase the process of reducing NO3- to NH3 on Cu-0 is an exothermic reaction, and that the adsorption process of NO3- on Cu-0 is the rate-determining step.

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