Photocatalytic Activity Of TiO₂-based Nanorod Arrays

Energy shortage and environmental pollution problem are the obstruction which hindered human's development in today's society.As the the burning of fossil fuels will lead to the greenhouse effect and produce a series of pollutants,the shortage of fossil fuel also makes people pay more attention to find new sources of energy to replace fossil fuels.Hydrogen energy which is a clean,environmentally friendly and low cost energy attracts people's attention.Watersplitting is a kind of simple and sustainable way to produce hydrogen.Compared to other photocatalytic material,TiO₂ is a non-toxic,cheap and not easy to be light corrosion materials.Thus TiO₂ is widely used by people.But as the TiO₂ material has a wider band gap and only could use the rarely ultraviolet light in the sunlight,for these reasons the water efficiency of TiO₂ material is not high.Improving the efficiency of TiO₂ materials is of great significance.At present,the ways of modification,doping and composite methods were used by researchers to improve the watersplitting performance of TiO₂ materials.This topic is deeply researched on TiO₂ nanorods array to improve the performance of watersplitting.TiO₂ nanorods grown on FTO through hydrothermal method,then improve the watersplitting performance of the TiO₂ nanorods by enhance the surface of it;WO₃ materials was prepared through magnetron sputtering and electrochemical deposition method;By deposited WO₃ on TiO₂ nanorods can synthesis compound TiO₂-WO₃ nanorods arrays which has a higher watersplitting performance.The main work is as follows:1.Through TiCl₄ treatment and water treatment,TiO₂ nanoparticles could attached on the surface of TiO₂ nanorods array,which has a larger surface and larger contact area surface in solution,it can significantly improve the efficiency of watersplitting.Compared with pure TiO₂ nanorods array,the photoelectric conversion efficiency of TiO₂-TiCl₄ nanorods array and TiO₂-H₂O nanorods array are increased by 25%and 250%respectively.When illumination time is at 90min,the hydrogen production of pure TiO₂ nanorods array is 0.44mL/cm²,TiO₂-TiCl₄ nanorods array is 0.52 mL/cm² and TiO₂-H₂O nanorods array is 0.85 mL/cm.2.The WO₃ materials was prepared through magnetron sputtering method and electrochemical deposition.Through different magnetron sputtering time and annealed temperature different property WO₃ films can be prepared.In our experimental,magnetron sputtering at 15 min and annealed temperature at 450? are the proper parameters to prepare WO₃ film.3.Different amount of WO₃ was deposited on TiO₂ nanorods array through electrochemical deposition method,the best deposition power that composite WO₃ with TiO₂ nanorods is 2C.As we can seen from the photoelectric catalytic properties that the oxygen production of TiO₂-2C WO₃ nanorods array is 3.09 mL which is higher than TiO₂ nanorods array oxygen production 0.24 mL.The surface of TiO₂ nanorods arrays increased after TiCl₄ treated,then deposit 2C WO₃ on TiO₂-TiCl₄ nanorods,the achieved TiO₂-TiCl₄-2C WO₃ nanorods array oxygen production is 4.24 mL which is obvious enhanced than TiO₂-TiCl₄ and TiO₂-2C WO₃ nanorods array when the illumination time is 80min.