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CdTe‐based thin film solar cell has been modeled and enumerated with a thin CuInTe2 (CIT) current booster layer. CdTe‐based n‐CdS/p‐CdTe/p+‐CIT/p++‐WSe2 heterojunction device is evaluated for the highest performance. It is revealed that physical parameters such as thickness, doping, and defects of the CIT layer have a significant influence on the performance of the CdTe solar cell. The device shows an efficiency of 37.46% with an open‐circuit voltage, VOC, of 1.102 V, short‐circuit current density, JSC, of 38.50 mA cm−2, and fill factor, FF, of 88.30%. The use of the photon recycling technique with a Bragg reflector with 98% back and 95% front reflectance only provides an efficiency of ≈44.3% with a current of 45.4 mA cm−2. These findings are very hopeful for the production of efficient CdTe solar cells in the near future.

Abstract Thin films of copper indium disulphide (CuInS 2 ) were grown on Ti substrates by sulpherisation of Cu–In precursors prepared by sequentially electrodeposited Cu and In layers. CuInS 2 films were characterised using X-ray diffraction (XRD), scanning electron micrographs (SEM), diffuse optical reflectance, spectral response and capacitance–voltage ( C – V ) measurements. It was observed that the Cu/In atomic ratio of initial Cu–In precurser determines the composition of the CuInS 2 films. XRD measurements revealed that single-phase polycrystalline CuInS 2 thin films can be obtained by optimising the thickness of the Cu and In layers. SEM showed that polycrystalline CuInS 2 thin films are having crystallites of size of ∼1–3 μm. Thin film of ZnSe was electrodeposited on CuInS 2 film in order to fabricate a solar cell. CV and photovoltaic characteristics established the formation of the CuInS 2 /ZnSe heterojunction.

Abstract Poly(3-hexylthiophene) formed gels and showed liquid crystalline structures at high concentrations. The absorption properties of poly(3-hexylthiophene) showed dramatic changes during gelation, which is an indication of strong intermolecular π-electronic coupling of the ordered self-assembled poly(3-hexylthiophene) gels. The effect of conformational transitions on the photovoltaic properties of solution-processed poly(3-hexylthiophene)/fullerene blends have been studied in this paper. It is shown that the photovoltaic performance is strongly affected by gelation, which alters the morphology of the photoactive layer. Device optimization yields solar cells with a power conversion efficiency of 4.0% under standard test conditions (AM 1.5, 100 mW/cm 2 ).

Supercapatteries are contemporary electrochemical energy‐storage devices that bridge the gap between the conventional supercapacitors and rechargeable batteries. Supercapatteries utilize battery‐type electrode‐active materials for their charge storage. Among the various futuristic materials, transition‐metal dichalcogenides receive prominent attention due to their excellent charge‐storage capabilities. Herein, the microwave‐assisted hydrothermal synthesis of layered two‐dimensional (2D) nickel sulfide nanosheets (NSN) and their application as electrode‐active materials in high‐performance asymmetric supercapatteries are reported. The layered 2D architecture is preferred for the electrode‐active materials as the layered electrode nanostructure provides a hindrance‐free movement to the electrolyte ions through it during the charge‐storage process that include intercalation/deintercalation mechanisms. The electrochemical thermal stability of the 2D NSN electrode reveals that its stability in KOH (aqueous) electrolyte is better than that in LiOH (aqueous) and NaOH (aqueous) electrolytes. The supercapattery electrode synthesized using 2D NSN exhibits excellent electrochemical charge‐storage performances bearing a maximum specific capacity of 594.77 C g−1 (an equivalent mass‐specific capacitance of 991.29 F g−1) in 2 M KOH (aqueous) electrolyte. The electrochemical cycling performance of the 2D NSN electrode shows a stability over 40 000 cycles without any significant capacity loss. An asymmetric supercapattery device fabricated with 2D NSN electrode as positrode and activated carbon as negatrode exhibits a maximum mass‐specific capacity of 143.58 C g−1 with a corresponding energy density of 29.91 Wh kg−1 in 2 M KOH (aqueous) electrolyte.

Abstract The optical properties of a new type of electrochromic material based on the reversible electrodeposition of Bi have been investigated. This electrochromic material system is being investigated for both low and high information flat panel display applications. Electrochemical devices based on the reversible electrodeposition of bismuth were fabricated using an aqueous electrolyte gel containing bismuth chloride, copper chloride, and lithium bromide. A cell structure of glass substrate/ tin oxide/ gel electrolyte/ porous carbon was employed. Optical measurements showed a spectral reflective contrast of greater than 60% in the visible spectrum. Visible reflectance could be controlled over a wide range of gray shades by controlling the writing voltage at a fixed write time or the writing time at a given voltage. The maximum reflective contrast was 67%. Depending on the display application, the electro-optical properties could be tailored by adding controlled amounts of Cu to the formulation.

Abstract Research on biofuels has been focused on improving yield of the conversion process while reducing the capital cost. Currently, 88% of the US ethanol production capacity and 96% of the planned expansion of capacity utilizes a dry milling process, which has a higher ethanol yield and a lower capital cost per gallon capacity than a wet milling process. However, the fact that all the corn ethanol plants that were bankrupted or idled during the 2008 economy recession used dry milling processes while all the plants that used wet milling processes had survived suggests that the efficiency driven approach may be flawed. This paper compares the economic performances of a typical dry milling plant with those of a typical wet milling plant under scenarios when market conditions are favorable or unfavorable to the corn ethanol production. The results show that the wet milling plant exhibits better performance under both scenarios due to its operational flexibility (e.g. having starch, high fructose corn syrup, gluten meal, gluten feed, and corn oil in its product portfolio). It is argued that the development of biofuel technologies should take operational flexibility into consideration in order to absorb disruptions from unexpected feedstock supply and volatile market conditions.

Carbon nanotubes (CNTs) are a promising conductive additive for Li‐ion batteries. However, good dispersion of agglomerated CNTs (ACNTs) still remains challenge. Herein, a binder‐assisted dispersion of ACNTs is demonstrated to efficiently construct a homogeneous conductive network in LiFePO4 cathodes. The addition of polyvinylidene fluoride (PVDF) significantly reduces the size of ACNT agglomerates, which leads to better dispersion of ACNTs in N‐methyl‐pyrrolidone. The LiFePO4 electrodes with conductive networks constructed from PVDF–ACNT suspensions exhibit superior electrode performance, as compared to those using the commercial CNT slurry.