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Abstract: Thin films of delafossite of CuAlO2 laminar crystals on metal substrates (Ni plates) were prepared by sol–gel processing and subsequent thermal treatment in vacuum. The influence of annealing treatment on surface morphologies and structure of the samples is discussed. Field-emission scanning electron microscope (FESEM) shows the laminar surface architecture of the as-prepared CuAlO2 thin films. The electrical property of sample was investigated by current–voltage analysis, which indicates that a rectifying junction between CuAlO2 film and metal substrate is formed and forward current exceeds reverse current by a factor of up to three. Otherwise, the photoelectrochemical characteristics recorded under 250mW/cm2 illumination show that the as-prepared thin film electrode which was annealed at 1150°C for 4h in vacuum possesses the highest photocurrent density, which is 0.7mA/cm2 at 0V vs Ag/AgCl. [Copyright &y& Elsevier]

Abstract: Nanostructured titanium dioxide (TiO2) thin films have been prepared on metal substrates using a facile layer-by-layer dip-coating method. The phase structure and morphologies of preparing samples were characterized by means of X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The results confirm that films are highly crystalline anatase TiO2 and free from other phases of titanium dioxide. Scanning electron microscopy (SEM) shows that the nanoparticles are sintered together to form a compact structure. The electrical properties of samples were investigated by cutternt–voltage analysis, the result indicates that a rectifying junction between the nanocrystalline TiO2 film and metal substrate was formed. The photoelectrochemical characteristics recorded under 1.5AM illumination indicates that the as-fabricated thin film electrode possesses the highest photocurrent density at 450°C, which is 1.75mA/cm2 at 0V vs. Ag/AgCl. [Copyright &y& Elsevier]

Abstract: Cuprous oxide (Cu2O) microcrystals have been successfully synthesized via a facile electrochemical method in alkaline NaCl solution with copper plate and graphite slice as electrodes and Na2Cr2O7 as additive. The as-synthesized products have been systematically studied by X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), selected area electron diffraction (SAED) and ultraviolet–visible spectrum (UV–vis). The results indicate that the pH value, temperature and potential play important roles in the morphology control besides the crystal habits of Cu2O. The possible mechanism has been explored in the article. [Copyright &y& Elsevier]