Study On Fabrication,modification And Photoelectrochemical Property Of TiO₂ Nanorods Array

The use of solar energy for water splitting is an effective way to alleviate the energy crisis and improve environmental pollution,and the study of thin film made by metal oxide semiconductor functioning as catalyst for photoelectrochemical water spillting is under great concerns,in which the most critical part is to exploit inexpensive semiconductor photoanode materials with high efficiency.Nano-semiconductor TiO₂ is non-toxic,cheap and chemically stable.In addition,TiO₂ has good carrier transport efficiency so that it's an ideal photoelectric and photocatalytic material.In the field of photoelectrochemical water splitting,TiO₂ materials with various morphology have been extensively explored.The structure of TiO₂ nanorods is well favored by its good performance of charge separation,charge transport and light absorption.In addition,many researchers are constantly exploring the modification of TiO₂ nanomaterials.In this paper,considering the influence of energy level matching on the photoelectrochemical properties of semiconductor materials and the modification on semiconductor materials by hydrogenated treatment,the heterojunction structure composed of TiO₂ nanorods and ZnO nanoparticles was elaborately designed and then treated with hydrogenation.The obtained hydrotreated TiO₂/ZnO heterojunctions were Mainly researched from the following two aspects:?1?The film of TiO₂ nanorods was synthetised by hydrothermal method.The morphology of TiO₂ nanorods was investigated by studying the amount of tetratitrobutyl titanate?TBOT?dosage and then the selected optimal TiO₂ nanorods were prepared for the subsequent heterojunction growth.A two-step method of depositing seed crystals and hydrothermal growth was used to grow TiO₂/ZnO heterojunction structure.The morphologies of TiO₂/ZnO heterojunction were researched by studying the concentration of zinc acetate,which is functioned as precursor for ZnO,and then determine the optimum concentration of zinc acetate.The synthetical characterization and photoelectrochemical properties of TiO₂/ZnO heterojunctions were finally performed.?2?Optimizing the fabrication process of heterojunction structure by a more simple method of solution coating,which achieve the goal in one time,and then improve the photoelectrochemical properties of TiO₂/ZnO heterojunction by hydrogenated treatment.The morphologies of TiO₂/ZnO heterojunction were investigated by controlling the amount of zinc acetate,and then the best TiO₂/ZnO heterojunction was optimized by hydrothermal treatment.All the heterojunctions and hydrogenated heterojunction were characterized by synthetical characterization and photoelectrochemical properties analysis.The results showed that the TiO₂/ZnO heterojunction with optimal morphology,optical and photoelectrochemical property was obtained when the amount of zinc acetate solution was 5.0 mM*1.0 mL.What's more,the hydrogenated TiO₂/ZnO heterojunction presented obviously enhanced absorbance intensity in the wavelength of visible light and better photoelectrochemical properties among all.