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For a dye-sensitized solar cell with a near-infrared squaraine (SQ1) sensitizer, the photovoltaic performance was enhanced remarkably with a reflective luminescent down-shifting (R-LDS) layer to increase the light-harvesting efficiency at the wavelength region 400-550 nm where the SQ1 dye has weak absorption. Relative enhancements greater than 200% in IPCE near 500 nm and 40-54% in JSC were achieved with red phosphor CaAlSiN3:Eu(2+) as the LDS material, attaining 5.0 and 4.8% overall efficiencies of power conversion for the R-LDS layer coated on the counter electrode (front illumination) and working electrode (back illumination), respectively.

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TiO2 deposited on a membrane of Ag fibers was prepared as a photoelectrochemical cell electrode. Ag fibers were made by reduction of Ag complexes on cellulose fibers, followed by burning out the template. TiO2 photocatalyst layers were grown on the fibers by electrophoretic deposition of TiO2 nanoparticles. Ag fibers could be uniformly deposited. Photocatalytic tests by dye decomposition and electrochemical impedance spectroscopy (EIS) under UV illumination demonstrate that Ag fibers act as a good substrate that provides both high surface area and good separation of photogenerated electron−hole pairs and causes the enhancement of photocatalytic activity in comparison with a thin film of TiO2.

Highly sensitive flexible humidity sensors based on graphene quantum dots (GQDs) were developed. The GQD sensors have potential for application in wearable electronics and RH monitoring.

We report a robust method of hot addition (HAM) to prepare methylammonium lead trichloride (MAPbCl3) and Mn-doped MAPbCl3 (Mn:MAPbCl3) perovskite nanocrystals (PeNCs) for application in luminescent solar concentrators (LSCs). The HAM, which is free of solvent and operates at high temperatures, is applicable to the synthesis of highly crystalline and stable organic–inorganic PeNCs with tunable optical properties. The Mn:MAPbCl3 PeNCs showed a remarkable energy-transfer shift from 400 to 600 nm that enhanced the optical efficiency when these PeNCs were incorporated in an LSC with a silicon solar-cell module. An optical efficiency (OE) greater than 8% was achieved on incorporation of only 0.094 mass % Mn:MAPbCl3 PeNCs in the LSC. A Monte-Carlo ray-tracing simulation was developed to improve the understanding of the experimental results and estimate the ultimate device performance for future application in building-integrated photovoltaic devices.

Nanotechnology has significant contributions on developing modern industries, such as electronics, biomedical, materials, manufacturing, and energy industry. The changes introduced by nanotechnology, have currently extended to several areas for oil and gas industry, namely exploration, drilling, production, refining and enhanced oil recovery (EOR). This study focuses on attraction to the worldwide attention of nanotechnology and how this method effects oil breakthrough and improves EOR. This Study also implies that parameters such as rock types, crude oil types, nanoparticle types, concentrations, and sizes, have significant factors on recovery factor (RF) through improving key-parameters such as oil relative permeability, interfacial tension (IFT), wettability, transmissibility and particles retention.

Titanium oxide (TiO2)-based photodetectors were fabricated using a thermal oxidation technique. The effect of two different annealing temperatures on morphology, structure, and I-V characteristics has been investigated. TiO2/Si heterostructure exhibited diode-like rectifying I-V behavior both in dark and under illumination. Dependence in photoresponse on annealing temperature was observed that was related to effective surface area of quasi-one-dimensional TiO2 nanostructures. Fabricated TiO2/Si diodes in 850 °C as the lower annealing temperature showed higher responsivity and sensitivity compared with grown ones in 950 °C (R850 °C/R950 °C ∼ 5 and S850 °C/S950 °C ∼ 1.6). Rather good photoresponse and simple fabrication process make the 850 °C-TiO2/Si diode a promising candidate for practical applications.