TiO2包覆不同微结构纳米碳纤维薄膜电极的光电化学性能  

Photoelectrochemical Properties of TiO_2 Coated on Carbon Nanofibers with Different Microstructure Film Electrodes

作　　者：李志州[1] 崔晓莉[2] 郑俊生[3] 王庆飞[1] 

机构地区：[1]河北师范大学化学与材料科学学院,石家庄050016 [2]复旦大学材料科学系,上海200433 [3]华东理工大学化学工程联合国家重点实验室,上海200237

出　　处：《高等学校化学学报》2008年第6期1195-1199,共5页Chemical Journal of Chinese Universities

基　　金：国家“八六三”计划(批准号:2006AA05Z121);国家自然科学基金(批准号:20673028,90406024);2006年上海市浦江人才计划;上海市重点学科建设项目(批准号:B113);华东理工大学化学工程联合国家重点实验室开放课题资助

摘　　要：采用溶胶-凝胶法制备了TiO2包覆不同微结构的纳米碳纤维(Carbon nanofibers,CNF),包括板式纳米碳纤维(Platelet-CNF,PCNF)和鱼骨式纳米碳纤维(Fish-bone-CNF,FCNF)的复合薄膜电极.用光电流作用谱和光电流-电势图等方法研究了复合薄膜电极的光电化学性能.研究结果表明,复合薄膜电极表现出n型半导体特征,薄膜中CNF的存在有助于光生电子和空穴有效地分离,提高了光电转换效率,TiO2包覆PCNF薄膜电极在可见光范围内存在明显的光电响应.Novel nanocomposites of TiO2 and two kinds＇ carbon nanofibers with different microstructure were prepared by sol-gel method. The nanocomposites were studied via SEM, XRD, and photoelectrochemistry. The potential dependence of photocurrent and the photocurrent transients indicate that the nanocomposite shows characteristics of n-type semiconductor. The experimental results demonstrate that the PCNF/TiO2 shows a higher photoelectrochemical response and sensitivity for visible light illumination than FCNF/TiO2 and pristine TiO2. This is likely because of the specific microstructure of the PCNF, which possesses large numbers of active edge sites and provides many favorable sites for electron transfer as well as a very large working surface area. The significant enhancement of the photoelectrochemical response of the CNF toward visible light responses may result from the difference of their morphologies as well as their textural properties and crystalline structure. The results show that PCNF and FCNF are thus very promising candidates for developing a class of ideal and novel modified photoelectrodes.

关 键 词：TiO2复合薄膜电极 纳米碳纤维 光电化学 光电转换效率(IPCE) 

分 类 号：O646[理学—物理化学]