Study On Preparation Of Nanomaterials By TiO₂ Nanotube Array Template

TiO₂ nanotubes have higher aspect ratio,large specific surface area and faster electron transport capability,making it widely used in the fields of catalysis,sensors and solar cells.Anodic oxidation method can effectively prepare TiO₂ nanotube arrays.TiO₂ nanotube arrays can be used alone or as templates to prepare other nanomaterials.In this paper,TiO₂ nanotube array templates were prepared by anodic oxidation,and metal Co,Ni and Cu nanowires were grown using TiO₂ nanotube arrays as templates.In addition,the research of filling cobalt ferrite nanowires with TiO₂ nanotube arrays as template was performed.1.The TiO₂ nanotube array template was prepared by anodic oxidation method.The pore size and length of the TiO₂ nanotube array template were controlled by changing the voltage and oxidation time,and its growth rules were summarized.Characterized by scanning electron microscopy,the pore size and tube length of the TiO₂ nanotube array template were found to be proportional to voltage and oxidation time.2.Metal Co,Ni and Cu nanonets were prepared on the surface of TiO₂ nanotube array template by direct current deposition and alternating current deposition.It has been found that direct current deposition of metal nanonets grows faster,but the surface is prone to nanoparticle impurities.The structure of the metal mesh prepared by the alternating current deposition method is relatively perfect,but the growth rate is slow.The metal meshes produced by the two electrodeposition methods have a large area,uniform pores,and the pore distribution of the nanomesh is consistent with the pore distribution of the TiO₂ nanotube array template,indicating that the nanowires are longer than the nozzle wall of the TiO₂ nanotube array template.Because the wall of the TiO₂ nanotube array template is thin and has semi-conductor properties,it produces tip feature that give preferential electrodeposition at the wall of the nozzle.3.Fill the CoFe₂O₄ nanowires in the TiO₂ nanotube array template by soaking,drying and annealing,and discuss the effect of different concentrations of the mixed solution on the filling rate of the TiO₂ nanotubes.It was found that high concentrations of the mixed solution can be filled with linear CoFe₂O₄ nanomaterials in the TiO₂ nanotube array template.A low concentration of the mixed solution fills the discontinuous CoFe₂O₄ nanomaterials in the TiO₂ nanotube array template.when the mixed solution is reduced again at the concentration.The filling rate of CoFe₂O₄nanoparticles in the TiO₂ nanotube array template decreases,showing an isolated dispersion.TiO₂ has high biocompatibility and strong chemical stability,so it is a good choice as a template material.Due to its high surface area and high porosity,metal nanowebs exhibit good catalytic and electron transport properties.CoFe₂O₄ nanowires have large magnetic anisotropy,proper staturation magnetization and good chemical stability,so it have a good application prospect in high-density magnetic recording.Therefore,the preparation of metal nanoweb structures and CoFe₂O₄ nanowires using TiO₂ nanotube arrays as templates has important implications in application.