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Heat-assisted PbS/TiO 2 thin films with different reaction temperatures were prepared. Microstructure, morphology, optical and photoelectron-chemical properties of the as-synthesized thin films were investigated systematically. For the PbS/TiO 2 thin films with reaction temperature changing from 10 to 95 °C, PbS particles obtained by successive ionic layer adsorption and reaction are galena phase, the mean size of PbS particles decreases firstly and then increases, the coverage of PbS particles on surface increases. At the same time, red shift in the adsorption edges from 416 to 594 nm has been detected, and the optical band gap E g decreases from 3.58 to 2.88 eV. What's more, the intensity of photoluminescence increases firstly and then decreases. The photochemistry measurement suggests that the sample prepared at 60 °C possesses the highest photocurrent in the first test cycle. However, the value of photocurrent decreases immediately with increasing the test cycle. The effect of the reaction temperature on the microstructure, morphology, optical and photoelectron-chemical properties of PbS/TiO 2 thin films have been discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract: Nanostructured CuO film was prepared using glass or stainless steel slices as substrate via a simple ammonia-assisted solution route at 60°C. The obtained CuO film was made up of well-crystallized nanosheets of 50–360nm in thickness and 0.7–4.5μm in width. The reaction time and the substrate have significant effects not only on the thickness, width, arrangement of the nanosheets but also on the morphology and the thickness of the films. The CuO film was characterized by SEM, TEM, XRD, IR, and Raman spectroscopy techniques. [Copyright &y& Elsevier]

TiO 2 nanotubes arrays (TiO 2 -NTAs) layers were successfully formed by electrochemical anodization on a titanium (Ti) surface in fluorine-containing electrolytes under different processing voltages and annealing temperatures. The formed TiO 2 -NTAs layers annealed at different temperatures were compared in terms of their morphologies, structures and band gaps. Their wetting abilities, photo-induced hydrophilicities and photocatalytic performances were also evaluated. It was found the sample anodized at 40 V for 2 h have the most uniform surface morphology. The TiO 2 -NTAs structures annealed at 600 °C for 2 h in air show multiphase crystallinity and have the narrowest band gap (2.89 eV). These structures have noticeable nanowires on the top of the nanotubes. Their photocatalytic activity, tested by degradation of aqueous methylene orange solutions under UV light illumination for 2 h, is the highest among all samples (degradation efficiency was 89.05%). Specimens annealed at 200, 400 and 800 °C show light-induced hydrophilicity. However, small contact angle change was observed when samples were annealed at 600 °C. [ABSTRACT FROM AUTHOR]

Abstract: Various ZnO architectures like novel flowerlike structures radially assembled by rods, nails or towers and novel radialized bundled tubular structures with diverse diameter in entire length were controllably synthesized with different amine precursors by a simple surfactant-free hydrothermal process. It suggests that diverse amine sources, which possibly have different hydroxyl ion releasing rate contributing to different reaction rates, probably play an importance role in controlling the assembly of different ZnO architectures, besides temperature and time. X-ray powder diffraction (XRD) results prove the ZnO belonging to wurtzite structure and room temperature photoluminescence (PL) demonstrates a high quality of the products. [Copyright &y& Elsevier]