Preparation And Performance Of Photocatalysts Modified With Non Noble Metal For Effective Hydrogen Production From Water Splitting

The energy crisis and environment problems are considered as two major factors hindering the development of human being. Photocatalysis, which has been considered to have great potential for serving these two factors, could convert solar energy into clean energy, hydrogen via a simple process. Considering the current efficient photocatalysts modified by noble metal materials cost too high to be taken into practice, we studied the preparation and photocatalytic performce of non noble metal such as copper and nickel loaded traditional materials as TiO2 and CdS, and the cocatalyst free photocatalyst with high catalytic activity and good stability was also studied.In order to investigate the influence of modification of Cu species on the photocatalytic activity of TiO2, P25 was taken as the carrier and the hydrothermal reduction method, impregnation combustion method and impregnation combustion reduction method were applied for preparing Cu or its oxides modified photocatalysts. Through the XRD, UV-Vis DRS, BET and TEM results, the influence of different modification on catalyst crystal type, band structures, surface and pore structures have been investigated. The different performances of photocatalytic hydrogen production were also discussed.The photocatalysts with metallic nickel loaded on the surface of cadmium sulfide were prepared via a simple hydrothermal reduction method in this paper. Characterization methods of the XRD, UV-Vis DRS, BET, TEM and XPS were undertaken to verify the as-prepared catalyst for the chemical composition, band structures, pore structures and surface properties. Photocatalytic activity tests were also taken to investigate the performance of the prepared catalysts. We found that when using 10 vol% lactic acid as sacrificial agent, loading 5 wt% nickel, the hydrogen production activity of cadmium sulfide was increased by more than 5 times, even better than the one with 0.5 wt% platinum as cocatalyst. Besides, through the XPS results, the nickel was found playing a different role in the lactic acid from other traditional sacrificial agents during the photocatalytic process.The polymerizable complex method was undertaken for preparation of noble metal free layered perovskite K0.5La0.5Bi2Ta2O9, and protonation for H-K0.5La0.5Bi2Ta2O9. The ICP, XRD, TEM, UV-Vis DRS and other methods are used to discuss the chemical composition, material morphology, catalyst structure and optical absorption ability. The influence of different synthesis temperatures and sacrificial agent on H-K0.5La0.5Bi2Ta2O9 hydrogen production activity was investigated via photocatalytic activity tests. The results indicated that the prepared layered compounds were of high photocatalytic activity without cocatalysts and sacrificial agents. The photocatalytic hydrogen production rate was 232.6 μmol·h~-1.