Preparation And Characterization Of Molybdenum-based Materials As Photo-and Electro-catalysis

Molybdenum-based catalysts have high catalytic activity and abundant reserves,which have showed great application potential in photocatalytic degradation,photocatalytic hydrogen evolution,electrocatalysis,battery electrode and other fields.This paper starts from MoO₃.On one hand,MoO₃ was modified to introduce oxygen vacancies to improve its catalytic performance.On the other hand,MoO₃ was used as the precursor to prepare 1T-MoS₂ materials,with hydrothermal method used as the preparation method.It is expected to realize the safely and environmentally friendly preparation of 1T-MoS₂ materials.The main work contents are as follows:（1）Firstly,MoO₃ was prepared by precipitation method.Then,MoO₃ was modified by surface reduction modification with ascorbic acid as the modifier,and the contents of oxygen vacancies of MoO_3-x was controlled by controlling the modification time.Finally,the photocatalytic degradation activity of the prepared MoO₃ and MoO_3-x-x were tested using rhodamine B as the simulative pollutant.The degradation efficiency of MoO_3-x-x is much higher than that of MoO₃.This is because a large number of oxygen vacancies were introduced into MoO_3-x after surface reduction modification,which improved MoO_3-x’s oxidizability,reduced MoO_3-x’s optical band gap energy and reduced the recombination ability of electron hole pairs,and thus improved MoO_3-x’s photocatalytic degradation activity.（2）1T-MoS₂ was prepared by low-temperature hydrothermal synthesis method with MoO3 serve as raw material and thioacetamide serve as sulfurizing agent.The influence of solvent,reaction temperature and urea addition amount on the morphology,composition and hydrogen evolution performance of MoS₂ were discussed.Test results show that MoS₂ with high contain of 1T-MoS₂ and regular shape was prepared under the condition of water as solvent,200℃as the reaction temperature,and 0.12 g as the of urea addition amount.The prepared MoS₂ showed the best hydrogen evolution performance because its smaller size and higher content of 1T-MoS₂,which provided more reactive sites for the hydrogen evolution reaction.