Preparation And Characterization Of Phosphide And The Application In Photocatalytic Hydrogen Production

Fossil fuels such as coal, oil and gas play an important role in the human economic and social civilization development. But these fossil fuels are finite and non-renewable. Due to extensive use of fossil fuels has caused severe energy crisis and related environmental problem. These problems seriously threat the survival of mankind. Therefore, in order to to replace traditional fossil fuels, it is imperative to develop new energy sources. Photocatalytic water splitting using solar energy is one of the effective ways to solve the above problems. Due to the limitation of semiconductor material structure, photocatalytic hydrogen production efficiency is not high, so modified semiconductor material is necessary. Loaded cocatalyst can improve the photocatalytic activity of semiconductor material. In this paper, CoP and MoP as co-catalyst to improve the photocatalytic TiO2 and CdS of hydrogen production activity are investigated.In this paper, CoP was prepared via phosphating the precursor using sodium hypophosphite. Photocatalytic hydrogen production test of CoP/TiO2 composite photocatalyst showed CoP can significantly improve photocatalytic activity of TiO2. When the loading amount is 2%, photocatalytic activity reached the maximum (22μmol-h’1), which is 22 times of pure TiO2. XRD and HRTEM showed CoP/TiO2 composite photocatalyst was successfully prepared. SEM, TEM showed the morphology of cocatalyst CoP were rod. UV-vis diffuse reflectance spectroscopy showed that the absorbance of CoP/Ti02 is higher than pure TiO2. With the increase of loading amount of CoP, the absorbance increased.CoP/CdS composite photocatalyst was prepared via coprecipitation. It is found CoP as a co-catalyst can effectively improve photocatalytic activity of CdS under visible light irradiation using lactic acid as a sacrificial agent. The loading amount of CoP has a great influence on photocatalytic activity of CdS. When the loading amount is 2%, the highest activity of hydrogen production (140μmol·h-1) is about 7 times of pure CdS and is 2 times of 1% Pt/CdS. XRD and HRTEM showed CoP/CdS composite photocatalyst was successfully prepared. SEM and TEM showed the morphology of cocatalyst CoP were rod. UV-vis diffuse reflectance spectroscopy showed the absorbance of CoP/CdS was higher than CdS in the visible region.MoP prepared via a temperature programmed reduction method. MoP/CdS composite photocatalyst was prepared via coprecipitation. Photocatalytic Hydrogen production activity showed that the activity of MoP/CdS greatly increased than CdS alone. The loading amount of MoP has a great influence on photocatalytic activity of CdS. When the loading amount is 2%, the highest activity of hydrogen production (78μmol·h-1) is about 4 times of pure CdS. XRD showed MoP/CdS was successfully prepared. UV-vis diffuse reflectance spectroscopy showed the absorbance of MoP/CdS was higher than CdS in the visible region.