金属螯合制备AZO@TiO2导电晶须及其性能研究

AZO@TiO₂导电晶须是一种导电性能好、白度高、价格低廉的导电材料。目前共沉淀法制备该材料难以实现锌铝元素掺杂均匀及近中性反应条件。本研究采用金属螯合法,以AlCl₃和ZnCl₂为原料,以乙酰丙酮为螯合剂,在无水乙醇中溶解得到稳定的金属螯合物前驱体溶液,再通过水解及煅烧在TiO₂表面包覆一层AZO导电膜制备AZO@TiO₂导电晶须。通过单因素试验探究了包覆比、掺杂比、乙酰丙酮的配比和煅烧温度对晶须导电性能的影响,并通过设计四因素三水平正交试验进一步优化工艺参数。借助扫描电子显微镜(SEM)、四探针测试仪、X射线衍射仪(XRD)、能谱分析仪(EDS)、透射电子显微镜(TEM)及热重分析仪(TGA)对所制得的导电晶须进行测试表征,结果表明,以此种方法制得的AZO@TiO₂导电晶须表面电阻率最低达到0.318kΩ·cm。

Preparation and property of electroductive AZO@TiO2 whisker by metal chelation

Electroductive AZO@TiO₂whisker is a conductive material with good conductivity,high whiteness and low price.At present,the preparation of this electroductive whisker is by coprecipitation method.However,the preparation of this material is difficult to achieve uniform doping of zinc and aluminum,and the pH value is difficult to control under near-neutral reaction conditions.The electroductive AZO@TiO₂whisker was prepared by using metal chelation,aluminum chloride and zinc chloride as raw material and acetylacetone as chelating agent.Metal chloride and acetylacetone was dissolved in ethanol solution,and formed a stable precursor solution.Then a layer of AZO conductive film was coated on the surface of TiO₂through hydrolysis and calcination.The effects of coating ratio,doping ratio,acetylacetone ratio and annealing temperature on whisker conductivity were investigated by single factor test.Furthermore,four factors and three levels of orthogonal test were designed to further optimize the process parameters.Samples were characterized by X-Ray diffraction(XRD),scanning electronic microscopy(SEM),energy dispersive spectrometer(EDS),transmission electron microscope(TEM)and thermogravimetric analysis(TGA).The results showed that the AZO@TiO₂had a lowest resistivity of 0.318 kΩ·cm.