TiO2/Bi2Se3复合材料的制备及光电化学性能  

Preparation and Photoelectrochemical Properties of TiO2/Bi2Se3 Composite Materials

作　　者：王超帅 仇怀利[1] 李思寒 张栋 沈周阳 李中军[1] Wang Chaoshuai;Qiu Huaili;Li Sihan;Zhang Dong;Shen Zhouyang;Li Zhongjun(School of Electronic Science and Applied Physics,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学电子科学与应用物理学院

出　　处：《半导体技术》2020年第1期52-57,共6页Semiconductor Technology

基　　金：国家级大学生创新创业训练项目(201910359073);安徽省自然科学基金资助项目(1708085ME122)

摘　　要：以二氧化钛(TiO2)为衬底,利用分子束外延(MBE)法制备了高质量的拓扑绝缘体硒化铋(Bi2Se3)薄膜。实验中,Bi与Se的流量比控制在1∶10左右,制得的薄膜厚度约为50 nm。利用反射高能电子衍射仪,对在TiO2(001)衬底上生长的Bi2Se3薄膜样品表面进行原位表征,可以看到清晰明亮的衍射条纹。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外-可见-近红外分光光度计和电化学工作站等测试手段对TiO2/Bi2Se3的晶体结构、表面形貌、光学和光电化学性质进行表征。结果表明,经Bi2Se3改性后的TiO2薄膜,在可见-红外区仍有较强的吸收峰,与纯TiO2薄膜相比,大大提高了其对太阳光的吸收利用率。在Bi2Se3和TiO2上分别蒸镀铟电极和金电极,将其制成光伏型光电探测器,并测试了样品在不同波长激光下的光响应特性及高频响应速度。A high-quality topological insulator bismuth selenide(Bi2Se3)film was prepared by molecular beam epitaxy(MBE)method with titanium dioxide(TiO2)as substrate.In the experiment,the Bi/Se flow ratio was controlled at about 1∶10,and the film thickness was about 50 nm.The surface of the Bi2Se3 film grown on the TiO2(001)substrate was characterized in situ by using a reflective high-energy electron diffractometer,and clear and bright diffraction fringes were observed.The crystal structure,surface morphology,optical and photoelectrochemical properties of TiO2/Bi2Se3 were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),UV-visible near-infrared spectrophotometer and electrochemical workstation.The results show that the TiO2 film modified by Bi2Se3 still has a strong absorption peak in the visible-infrared region,and its absorption and utilization of sunlight is greatly improved compared with the pure TiO2 film.Indium electrodes and gold electrodes were deposited on Bi2Se3 and TiO2,respectively,and fabricated into a photovoltaic photodetector.Then the photoresponse characteristics and high-frequency response speed of the samples under different wavelengths of laser were tested.

关 键 词：拓扑绝缘体 硒化铋(Bi2Se3) 二氧化钛(TiO2) 分子束外延(MBE) 光响应 

分 类 号：TN304.9[电子电信—物理电子学]