掺杂Ag提升TiO_2纳米薄膜光电性能研究

Photoelectric properties of TiO_2 nanostructured films enhanced by Ag doping

采用sol-gel法制备出Ag掺杂的TiO_2纳米薄膜,利用SEM、XRD、UV-Vis、XPS及电化学工作站等对其光学及光电特性进行表征,研究了掺杂浓度及退火温度对材料晶体结构、光学特性及光电性能的影响规律。结果表明:Ag的掺杂提高了材料的晶相转变温度,降低了材料禁带宽度,使吸收带边发生红移(约40 nm),有效提高薄膜对太阳光的利用效率。当Ag掺杂浓度为摩尔分数0.5%,退火温度为500℃时,材料表现出最佳的光电活性,光电流密度达0.38×10^(–3)A/cm^2,相较于纯TiO_2薄膜的光电流密度增大约41%,光电性能得到显著提升且稳定性良好。

Ag-doped TiO2 nanostructured thin films were prepared via sol-gel method.Their optical and photoelectric properties were characterized by SEM,XRD,UV-Vis,XPS and electrochemical workstation.The effects of doping concentration and annealing temperature on the crystal structure,optical properties and optoelectronic properties were studied.The results show:the doping of Ag increases the crystalline phase transformation temperature of the material,reduces the energy band of the material,causes the red shift of the absorption band edge(about 40 nm),and effectively enhances the utilization efficiency of the film under sunlight.When the Ag doping mole fraction is 0.5%and the calcination temperature is 500℃,the material exhibits the best photoelectric activity and the photocurrent density which is increased to 0.38×10–3A/cm2.Compared with the pure TiO2 film,the photocurrent density of Ag-TiO2 increases by about 41%,and it shows significantly improved photoelectric properties and good stability.