Synthesis Of InP-based Nanostructures And Their Photocatalytic Hydrogen Production Performances In Pure Water System

With the development of the world economy and the increasing energy demand,researchers have focused more on the use of solar energy.Thus,photodecomposition water for hydrogen evolution has become a hotspot in the field of new energy.Unfortunately,the low efficiency of hydrogen evolution by solar energy would restrict the wide application of photodecomposition water to a certain extent.Therefore,it is imperative to research and develop new photocatalysts with high efficiency of hydrogen evolution.In this thesis,the author firstly reviews the research status and some problems in several typical photocatalysts used for photolysis of water to produce hydrogen,and then mainly summarizes the research work during the master’s degree.Herein the author focuses on the efficient photocatalysts of InP-based nanoheterostructures with surface modification stratege,surrounding the substantial questions of spectral response and the separation and transfer of electron-hole pairs in photocatalytic hydrogen evolution system.The research contents and results involved are as follows:1.The route of syntheses for the SnO/In（OH）₃/InP heterostructural photocatalysts is proposed by using hydrothermal method.That is,a transition layer of In（OH）₃is formed on the surface of InP in the first hydrothermal process,and then the wide bandgap semiconductor SnO nanoflakes are deposited on the surface of In（OH）₃/InP for constructing the SnO/In（OH）₃/InP heterostructure through the secondary hydrothermal process.The stabity of metastable InP was significant enhanced in water by the protection of In（OH）₃and SnO.Besides,the precious metal Pt deposited on the InP surface improves the light absorption and fastens the seperation and transportation of photogenerated charges,and further promote the activity of catalyst on photocatalytic hydrogen evolution.The experimental results show that the as-prepared SnO/In（OH）₃/InP-Pt heterostructural photocatalyst can achieve a hydrogen evolution rate of 144.42μmol/g in a pure water system within 3 hours,which is 123.44 times higher than that of the In（OH）₃/InP（1.17μmol/g）under visible light irradiation.Meanwhile,no signs of decay for the hydrogen evolution rate of the photocatalyst are observed after 4 cycles,maintaining an excellent stability.2.Based on the above research,high purity InP nanoparticles as the main catalysts are synthesized by sodium hypophosphite reduction method,and a series of photocatalysts with InP@ZnO-Pt core-shell heterostructure are prepared by hydrothermal method.The experimental results show that the hydrogen evolution rate of the catalyst can reach 100.72μmol/g within 3 h under visible light irradiation,which is 4.3 times higher than that of the pure InP（23.42μmol/g）.The excellent photocatalytic activity of the InP@ZnO-Pt core-shell heterostructure should be attributed to the effective improvement of the separation and transportation of photogenerated carriers.