Laser-based synthesis of TiO2-Pt photocatalysts for hydrogen generation

The development of visible-light active titanium dioxide is one of the key challenges in photocatalysis that stimulates the development of TiO2-based composite materials and methods for their synthesis. Here, we report the use of pristine and Pt-modified dark titanium dioxide prepared via pulsed laser ablation in liquid (Nd:YAG laser, 1064 nm, 7 ns) for photocatalytic hydrogen evolution from alcohol aqueous solutions. The structure, textural, optical, photoelectrochemical, and electrochemical properties of the materials are studied by a complex of methods including X-ray diffraction, low-temperature nitrogen adsorption, electrophoretic light scattering, diffuse reflection spectroscopy, photoelectrochemical testing, and electrochemical impedance spectroscopy. Both the thermal treatment effect and the effect of modification with platinum on photocatalytic properties of dark titania materials are studied. Optimal compositions and experimental conditions are selected, and high photocatalytic efficiency of the samples in the hydrogen evolution reaction (apparent quantum yield of H2 up to 0.38) is demonstrated when irradiated with soft UV and blue LED, i.e., 375 and 410 nm. The positive effect of low platinum concentrations on the increase in the catalytic activity of dark titania is explained

Interfacial reactions in the system of MnTe-H2O

The thermodynamically possible reactions in MnTe-H2O system at room temperature have been studied. The potential–pH diagram has been plotted assuming quasi-equilibrium on interfacial boundary. The possible mechanism of formation and the composition of a surface in dependence on electrode potential and pH have been discussed and the stable conditions for manganese telluride, i.e. the specific area in the diagram (pH from −2 to 14 and potential from −1.5…− 1.1 to −0.9…−0.6 V) have been found. The obtained results may help optimize the conditions for electodeposition of manganese telluride thin films and for liquid chemical etching for the formation of interfacial boundaries

Interfacial reactions in the system of MnTe-H2O

The thermodynamically possible reactions in MnTe-H2O system at room temperature have been studied. The potential–pH diagram has been plotted assuming quasi-equilibrium on interfacial boundary. The possible mechanism of formation and the composition of a surface in dependence on electrode potential and pH have been discussed and the stable conditions for manganese telluride, i.e. the specific area in the diagram (pH from −2 to 14 and potential from −1.5…− 1.1 to −0.9…−0.6 V) have been found. The obtained results may help optimize the conditions for electodeposition of manganese telluride thin films and for liquid chemical etching for the formation of interfacial boundaries