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CuSbSe2 is a promising light‐harvesting material for solar cells, which shows advantages including low melting point, low cost, and environmental friendliness, as well as excellent optoelectronic properties. In this work, a three‐source co‐evaporation method is employed to deposit CuSbSe2 thin films for the first time. Well‐crystallized and pure‐phase CuSbSe2 films are obtained through a two‐stage co‐evaporation, and the reaction mechanism of CuSbSe2 is revealed based on the phase evolution during film deposition process. It is also found that the growth atmosphere during the high‐temperature stage of co‐evaporation deposition exerts a significant impact on the phase, composition, crystallinity, and optoelectronic properties of CuSbSe2 films. Eventually, a Mo/CuSbSe2/CdS/ZnO:Al (AZO)/Ag‐structured solar cell is successfully constructed, yielding a considerable power conversion efficiency of 1.83%. [ABSTRACT FROM AUTHOR]

One of the areas of research on materials for thin-film solar cells focuses on replacing In and Ga with more earth-abundant elements. In that respect, chalcostibite (CuSbS2) is being considered as a promising environmentally friendly and cost-effective photovoltaic absorber material. In the present work, single CuSbS2 phase was synthesized directly by a short-duration (2 h) mechanochemical-synthesis step starting from mixtures of elemental powders. X-ray diffraction analysis of the synthesized CuSbS2 powders revealed a good agreement with the orthorhombic chalcostibite phase, space group Pnma, and a crystallite size of 26 nm. Particle-size characterization revealed a multimodal distribution with a median diameter ranging from of 2.93 μm to 3.10 μm. The thermal stability of the synthesized CuSbS2 powders was evaluated by thermogravimetry and differential thermal analysis. No phase change was observed by heat-treating the mechanochemically synthesized powders at 350 °C for 24 h. By UV-VIS-NIR spectroscopy the optical band gap was determined to be 1.41 eV, suggesting that the mechanochemically synthesized CuSbS2 can be considered suitable to be used as absorber materials. Overall, the results show that the mechanochemical process is a viable route for the synthesis of materials for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Purpose: In the past several years, CH3NH3PbI3 perovskite material has been extensively evaluated as an absorber layer of perovskite solar cells due to its excellent structural and optical properties, and greater than 22% conversion efficiency. However, improvement and future commercialization of solar cells based on CH3NH3PbI3 encountered restrictions due to toxicity and instability of the lead element. Recently, studies on properties of lead-free and mixture of lead with other cations perovskite thin films as light absorber materials have been reported. The purpose of this paper was the fabrication of CH3NH3Sn1-xPbxI3 thin films with different SnI2 concentrations in ambient condition, and study on the structural, morphological, optical, and photovoltaic performance of the studied solar cells. The X-ray diffraction studies revealed the formation of both CH3NH3PbI3 and CH3NH3SnI3 phases with increasing the Sn concentration, and improvement in crystallinity and morphology was also observed. All perovskite layers had a relatively high absorption coefficient >104 cm−1 in the visible wavelengths, and the bandgap values varied in the range from 1.46 to 1.63 eV. Perovskite solar cells based on these thin films have been fabricated, and device performance was investigated. Results showed that photo-conversion efficiency (PCE) for the pure CH3NH3PbI3sample was 1.20%. With adding SnI2, PCE was increased to 4.48%. Design/methodology/approach: In this work, the author mixed tin and lead with different percentages in the perovskite thin film. Also, the preparation of these layers and also other layers to fabricate solar cells based on them were conducted in an open and non-glove box environment. Finally, the effect of [Sn/Pb] ratio in the CH3NH3Sn1-xPbxI3 layers on the structural, morphological, optical, electrical and photovoltaic performance have been investigated. Findings: CH3NH3Sn1-xPbxI3 (x = 0.0, 0.25, 0.50, 0.75, 1.0) perovskite thin films have been grown by a spin-coating technique. It was found that as tin concentration increases, the X-ray diffraction and FESEM images studies revealed the formation of both CH3NH3PbI3 and CH3NH3SnI3 phases, and improvement in crystallinity, and morphology; all thin films had high absorption coefficient values close to 104 cm−1 in the visible region, and the direct optical bandgap in the layers decreases from 1.63 eV in pure CH3NH3SnI3 to 1.46 eV for CH3NH3Sn0.0.25Pb0.75I3 samples; all thin films had p-type conductivity, and mobility and carrier density increased; perovskite solar cells based on these thin films have been fabricated, and device performance was investigated. Results showed that photo-conversion efficiency (PCE) for the pure CH3NH3PbI3sample was 1.20%. With adding SnI2, PCE was increased to 4.48%. Originality/value: The preparation method seems to be interesting as it is in an ambient environment without the protection of nitrogen or argon gas. [ABSTRACT FROM AUTHOR]

Organic photovoltaic devices have long been considered as an important alternative for coal-based energy technologies due to their low-cost, lightweight and flexible nature. However, the power conversion efficiencies of such cells are limited by thermalization and transmission losses, which can be overcome by stacking multiple cells in a tandem configuration. This approach allows utilization of the wider spectrum of solar light, helping in attaining the theoretical limits for single cell efficiency (~30%). However, the performance of such tandem organic solar cells depends largely on several factors, including the proper design of absorber, sub-cells and interconnecting layer materials. In this review, recent studies on the development of different fullerene, non-fullerene, small molecule acceptor based active layers have been reported. Also, some recent works in the field of the inorganic-organic hybrid tandem cells have been briefly discussed. The purpose of this review is manifold: to provide the readers with a comprehensive overview of past, current research, recent developments, and open problems of tandem organic solar cells. [ABSTRACT FROM AUTHOR]

Eco-friendly and efficient rectifying p-n diodes have been developed by using cost-effective and non-toxic tin monosulfide (SnS) thin films. Chemically stoichiometric tin monosulfide (SnS) thin films followed by titanium/gold (Ti/Au) bilayer contacts were deposited on Si substrates and then, the structures were treated by rapid thermal annealing process (RTP) at different temperatures. The impact of RTP treatment on the surface morphology and chemical composition of Ti/Au contacts and SnS films along with their electrical characteristics were investigated. The electrical measurements show that as compared to untreated Si/SnS/Ti/Au structures, the heat-treated structures typically at 200 °C possess low electrical resistivity and contact resistance of ∼3 × 10−2 Ωcm and ∼11 kΩ, respectively. Heterojunction formed between p-SnS and n-Si exhibited excellent diode characteristics and possess a high current flow in the order of milliamperes, and excellent rectification factor of 1177@ 5 V. [ABSTRACT FROM AUTHOR]

Abstract Structural, electronic and optical absorption spectrum properties of lead free organometal halide perovskite CH 3 NH 3 BiX 3 (X = I 2 Te, I 2 S, I 2 Se) as a new absorber for solar cells are studied in comparison to the well-known methylammonium lead iodide perovskite (CH 3 NH 3 PbI 3) by using first principle calculations. CH 3 NH 3 PbI 3 is known to be one of the major breakthrough in absorbing layers for solar cell material researches. These properties allowed this material to break records in the photoelectric conversion reaching 22% in Power Conversion Efficiency (PCE) in a short period of time, but this material have some drawbacks, putting obstacles for its commercialization. First one is the instability and the second one is the toxicity of lead. It was the reason why, the choice of Bi was the most appropriate to use in CH 3 NH 3 BiI 2 Te, CH 3 NH 3 BiI 2 S and CH 3 NH 3 BiI 2 Se as it is a non-toxic element and also for the fact that it does not induce a big difference in the electronic structure, being close to lead in the periodic table. Furthermore, for its high optical absorption in the visible obtained on CH 3 NH 3 BiI 2 Te, CH 3 NH 3 BiI 2 S and CH 3 NH 3 BiI 2 Se compounds. These advantages may suggest that halide perovskite CH 3 NH 3 BiX 3 (X = I 2 Te, I 2 S, I 2 Se) based bismuth could be a promising alternative to CH 3 NH 3 PbI 3. These results may provide a basis for future applications in photovoltaic domain. Highlights • Lead free organometal halide perovskite CH 3 NH 3 BiX 3 (X = I 2 Te, I 2 S, I 2 Se) as a new absorber for solar cells. • High optical absorption in the visible obtained on CH 3 NH 3 BiI 2 Te, CH 3 NH 3 BiI 2 S and CH 3 NH 3 BiI 2 Se compounds. • Halide perovskite CH 3 NH 3 BiX 3 (X = I 2 Te, I 2 S, I 2 Se) based bismuth could be a promising alternative to CH 3 NH 3 PbI 3. [ABSTRACT FROM AUTHOR]

Highlights • Silver nanoparticles (NSP) were synthesized in situ in a methacrylate resin (MetA). • The dispersions of NSP in MetA polymerized after ∼20 min at 80 °C. • The plasmonic band of the NSP was broaden by changing the reaction conditions. • Heat generation by NSP under irradiation can be used for harvesting solar energy. Abstract This study describes the synthesis and characterization of polymer-based nanocomposites to fabricate absorber materials for solar thermal collectors. Heat generation by nanosized silver particles (NSP) under irradiation with light of appropriate wavelength is exploited for an efficient harvesting of solar energy. NSP were synthesized by reduction of silver nitrate (AgNO 3) in a methacrylate resin. The photothermal conversion of solar energy into heat is optimized by increasing the overlap between the plasmonic band of the NSP and the spectral emission of the sun. Thus, the synthesis conditions were adjusted in order to broaden the plasmon absorption band of the resultant NSP. The UV–vis spectra of suspensions containing 300 ppm NSP exhibited a broad absorption band in the range between 360 and 1100 nm with three absorption peaks at 335, 440, and 700 nm. These absorption bands are associated to the presence of triangular NSP, which was confirmed by TEM microscopy. The resins containing NSP were activated with benzoyl peroxide and polymerized after 20 min at 80 °C. The photothermal conversion effect of the nanocomposites was assessed by monitoring the temperature increase with fine thermocouples embedded in 2-mm thick specimens during irradiation with light of different wavelength. The temperature reached during irradiation of nanocomposites showing a very broad absorption band was 115 °C while that of the nanocomposites exhibiting a single peak was 102 °C. [ABSTRACT FROM AUTHOR]

Extreme ultra violet lithography (EUVL) is no longer a future technology but is going to be inserted into mass production of semiconductor devices of 7 nm technology node in 2018. EUVL is an extension of optical lithography using extremely short wavelength (13.5 nm). This short wavelength requires major modifications in the optical systems due to the very strong absorption of EUV light by materials. Refractive optics can no longer be used, and reflective optics is the only solution to transfer image from mask to wafer. This is why we need the multilayer (ML) mirror-based mask as well as an oblique incident angle of light. This paper discusses the principal theory on the EUV mask design and its component materials including ML reflector and EUV absorber. Mask shadowing effect (or mask 3D effect) is explained and its technical solutions like phase shift mask is reviewed. Even though not all the technical issues on EUV mask are handled in this review paper, you will be able to understand the principles determining the performance of EUV masks. [ABSTRACT FROM AUTHOR]

A method is described to determine the activity of non-pure positron emitters in a radionuclide production environment by assessing the 511 keV annihilation radiation concurrently with selected γ -lines, using a single High-Purity Germanium (HPGe) detector. Liquid sources of 22 Na, 52 Fe, 52 m Mn, 61 Cu, 64 Cu, 65 Zn, 66 Ga, 68 Ga, 82 Rb, 88 Y, 89 Zr and 132 Cs were prepared specifically for this study. Acrylic absorbers surrounding the sources ensured that the emitted β + -particles could not escape and annihilate away from the source region. The absorber thickness was matched to the maximum β + energy for each radionuclide. The effect on the 511 keV detection efficiency by the non-homogeneous distribution of annihilation sites inside the source and absorber materials was investigated by means of Monte Carlo simulations. It was found that no self-absorption corrections other than those implicit to the detector calibration procedure needed to be applied. The medically important radionuclide, 64 Cu, is of particular interest as its strongest characteristic γ -ray has an intensity of less than 0.5%. In spite of the weakness of its emission intensity, the 1346 keV γ -line is shown to be suitable for quantifying the 64 Cu production yield after chemical separation from the target matrix has been performed. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a versatile commodity polymer with a plethora of potential applications, in this work, short-chain branches of anhydride, amine, and various acrylate monomers with varying molecular weights were grafted onto PP using reactive extrusion. It was envisioned that such graft co-polymers can enhance the performance of PP making it a viable material such as water heating applications. The main interest herewith is to evaluate the occurrence of the grafting reaction and its effect on the thermal properties of the resulting graft co-polymers. Fourier Transform Infrared (FTIR), Differential Scanning Calorimeter (DSC), Polarized Optical Microscopy (POM), Thermogravimetric Analysis (TGA), gel content, and rheology tests were conducted to evaluate the effect of grafting on the performance of PP. DSC results showed a novel increase in crystallinity and crystallization temperature indicating a nucleating effect by the grafted chains. This is correlated with TGA and rheology results, where an increase in the temperature of maximum degradation and a reduction in the viscosity proved to be converging confirmations of grafting. The results clearly indicated successful grafting of PP which resulted in improved thermal stability that is essential for use in energy applications. [Display omitted] • Facile and novel grafting of short-chain monomers on PP. • Novel utilization of extrusion approach for grafting reaction. • Proposal of potentially excellent material for energy applications. • Enhanced PP thermal stability via in-situ extrusion grafting. • Outstanding improvement in crystallinity of grafted PP. [ABSTRACT FROM AUTHOR]

Highly porous polyetherimide (PEI) microparticles achieved by a spraying/coagulation process are candidate absorber materials for apheresis applications. Hydrophobic PEI surfaces tend to be rapidly coated with proteins when in contact with blood. Therefore, a hydrophilic modification of such particles is required. In this study, we explored the formation of porous, surface functionalized PEI microparticles by low molecular weight polyethyleneimine (Pei) or potassium hydroxide (KOH) in an integrated process combining chemical modification and particle formation. The integrated process resulted in smaller microparticles with diameters of 70 to 80 μm compared to the chemical twostep process. All particles exhibited similar bulk densities, ranging from 0.09 to 0.015 g cm-3, and average pore sizes around 180-250 nm. A successful modification of the particles' surface by both processing approaches could be confirmed by X-ray photoelectron spectroscopy measurements and microwetting experiments, where hydrophilic advancing contact angles of 57° to 64° were determined. Integrated particle processing further resulted in changes of the bulk properties, i.e. molecular weight, thermal decomposition behavior or glass transition temperature. Hydrophilic modified PEI microparticles have been successfully prepared by different approaches. In a next step their absorption capacity for uremic toxins will be investigated with regard to a potential application in blood detoxification. [ABSTRACT FROM AUTHOR]

Tin (II) sulphide (SnS), a direct band gap semiconductor compound, has recently received great attention due to its unique properties. Because of low cost, absence of toxicity, and good abundance in nature, it is becoming a candidate for future multifunctional devices particularly for light conversion applications. Although the current efficiencies are low, the cost-per-Watt is becoming competitive. At room temperature, SnS exhibits stable low-symmetric, double-layered orthorhombic crystal structure, having a = 0.4329, b = 1.1192, and c = 0.3984 nm as lattice parameters. These layer-structured materials are of interest in various device applications due to the arrangement of structural lattice with cations and anions. The layers of cations are separated only by van der Waals forces that provide intrinsically chemically inert surface without dangling bonds and surface density of states. As a result, there is no Fermi level pinning at the surface of the semiconductor. This fact leads to considerably high chemical and environmental stability. Further, the electrical and optical properties of SnS can be easily tailored by modifying the growth conditions or doping with suitable dopants without disturbing its crystal structure. In the last few decades, SnS has been synthesized and studied in the form of single-crystals and thin-films. Most of the SnS single-crystals have been synthesized by Bridgeman technique, whereas thin films have been developed using different physical as well as chemical deposition techniques. The synthesis or development of SnS structures in different forms including single-crystals and thin films, and their unique properties are reviewed here. The observed physical and chemical properties of SnS emphasize that this material could has novel applications in optoelectronics including solar cell devices, sensors, batteries, and also in biomedical sciences. These aspects are also discussed. [ABSTRACT FROM AUTHOR]

CuInS 2 absorber thin films were prepared by spray pyrolysis deposition at different substrate temperatures (250 °C, 300 °C and 350 °C) using an aqueous solution of CuCl 2 , InCl 3 and SC(NH 2 ) 2 at a precursor molar ratio of Cu:In:S=1:1.25:4.5. The effect of the substrate׳s temperature on the structural, morphological, optical and electrical properties of CuInS 2 thin films was investigated. The X-ray diffraction patterns showed that CuInS 2 has a tetragonal structure. The results show that the films deposited at 300 °C have improved electrical conduction and photocurrent values. When increasing the substrate׳s temperature the absorbance decreases while the band gap energy increases, as a combined effect of crystallinity, morphology and deviation from stoichiometry. [ABSTRACT FROM AUTHOR]

Abstract: Ternary Cu(Sb,Bi)(S,Se)2 compounds such as CuSbS2, CuSbSe2, CuBiS2, and CuBiSe2, are potential photovoltaic materials that contain earth abundant and low-cost elements. Employing an atomistic first-principles modeling within the density function theory we calculate the electronic and optical properties of Cu(Sb,Bi)(S,Se)2 compounds. We find that these four materials have indirect fundamental band gaps in the range of 1.1–1.7eV. The indirect gap nature is different to the previous experimental measurements (direct gap). Calculations reveal that these materials have strong optical absorption compared to chalcopyrite CuIn(S,Se)2 and kesterite Cu2ZnSn(S,Se)4. The strong absorption of these compounds is explained by the localized p-states of cation Sb/Bi in the lower region of conduction band. Thereby, ternary Cu(Sb,Bi)(S,Se)2 compounds have the potential to be used as absorber material in thin-film PV technologies. [Copyright &y& Elsevier]

The paper discusses the effect of quasiisostatic hot pressing conditions in compressible elastic media in the temperature range 1050-1850°C on the properties and phase composition of pellets made of dysprosium hafnate and dysprosium titanate, which are considered to be promising absorber materials for control rods of water-cooled water-moderated nuclear reactors. The hot pressing conditions that promote production of high-density radiation-resistant pellets are determined. The mechanisms of DyTiO and DyHfO phase formation are discussed. The microhardness of the absorber material after hot pressing at different temperatures is determined. [ABSTRACT FROM AUTHOR]

We compared different commercially available materials that are 3D-printable for their suitability for making microwave absorbers by means of additive manufacturing, i.e., 3D printing. For this, we determined their complex permittivity, and, if applicable, the complex permeability. They are responsible for the RF losses within the material and, therefore, determine its usefulness as an absorber material. Further, we made SEM (scanning electron microscope) images of material samples showing the filling materials that have been used to achieve absorbing properties. [ABSTRACT FROM AUTHOR]

Nowadays, textiles especially nonwovens see a strong growth in automotive market. Generally, the development of automotive nonwovens mainly focus on comfort, safe and green. To develop new, extremely sustainable vehicles, the use of recycled materials and other renewable raw materials continue to grow. In this article, latest developments of nonwoven absorber materials, filtration materials and battery separator were introduced. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) have significantly reduced the overall cost of solar energy system, making solar oriented devices universally clean and green energy source. However, to make OSCs more competitive in diverse photovoltaic (PV) technologies, it is essential to attain high efficiencies by analyzing novel materials and realizing optimal arrangements of donor–acceptor materials. In this paper, we attempt to show a terse depth insight of OSCs by investigating three novel architecture schemes with special emphasis on improving the power conversion efficiency. The materials include include i) poly (3-hexylthiophene):[(6,6)]-phenyl C61 butyric acid methyl ester (P3HT:PCBM), ii) thieno [3,4-b] thiophene-alt-benzodithiophene [6,6]:-phenyl-C61 butyric acid methyl ester (PTB7:PCBM), and iii) poly{4,4′-bis(2-ethylhexyl) dithieno [3,2-b:2′,3′-d] silole-alt-5,6-difluoro-4,7-bis (4-hexylthiophen-2-yl)-2,1,3-benzothiadiazle): [6,6]-phenyl-C61 butyric acid methyl ester (PDTS-DTffBT:PCBM), respectively. Results show that the extracted performance parameters including short circuit current (J SC) = 10.88 mA/m2, open circuit voltage (V oc) = 0.82 V, fill factor (FF) = 83.52 %, and efficiency (ƞ) = 7.49 % is highest for the second scheme among others. Different intermediate layers have also been analyzed with the objective to reduce the recombination losses and enhance the power conversion efficiency of the proposed cell. The impact of temperature on the overall ղ is also presented and it is discovered that high temperature reduces the performance of the solar cell. Furthermore, the performance of the proposed structure is compared with various kinds of OSCs and it is found that our design exhibit highest efficiency. The achievement of high efficiencies in this work may accelerate the practical applications of OSCs. [ABSTRACT FROM AUTHOR]

Full‐color reflective filters for large area applications with potentially unprecedented color saturation and excellent mechanical properties deposited by one‐step magnetron sputtering are proposed. Conventional reflective color filters with multiple layers of dielectric films cannot simultaneously produce a large area and good mechanical properties due to the complex multiple depositions and the difference in the thermal expansion coefficients among the material layers. Herein, full‐spectrum colors are generated by novel Mg‐based reflective color filters in a large area of 2 cm × 2 cm with a high hardness of 9.12 GPa, where the filters include an absorber layer with controllable optical constants and a reflective layer with an amorphous structure. The saturation and hue of the produced colors can be controlled by tuning the optical constants and the thickness of the absorber layer. Additionally, the hardness of the Mg‐based reflective color filters is increased by the reflective metallic glass layers because they are derived from the same material as the absorber layer. This paradigm can pave the way for the efficient fabrication of large area color filtering devices for diverse applications, such as surface decorations, optical components, color display devices, structural color printing, and photovoltaic cells with optimum efficiency. [ABSTRACT FROM AUTHOR]