K_2Ti_6O_(13)薄膜电极的制备及其光电化学  

Photoelectrochemical Investigation of K_2Ti_6O_(13) Thin Film Prepared by Sol-Gel Method

作　　者：胡煜艳[1] 钱清华[1] 李伟[1] 刘畅[1] 冯新[1] 陆小华[1] 

机构地区：[1]南京工业大学化学化工学院,江苏南京210009

出　　处：《过程工程学报》2007年第6期1236-1242,共7页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:20246002;20236010;20676062);国家杰出青年科学基金资助项目(编号:29925616);江苏省环保科技发展基金资助项目(编号:2005001-2)

摘　　要：采用溶胶-凝胶法制备了隧道状结构的K2Ti6O13薄膜电极.溶胶-凝胶法解决了K2Ti6O13与导电基材间结合差的难题,实现了该电极良好的导电性能.在此基础上,通过紫外-可见光吸收光谱结合电化学方法确定了K2Ti6O13薄膜的能带结构.溶胶-凝胶法制备的TiO2薄膜电极用于验证方法的可靠性,并作为K2Ti6O13薄膜结构和性能特征的参照系.实验结果表明,制备的K2Ti6O13薄膜电极禁带宽度为3.05eV,小于K2Ti6O13粉体的禁带宽度(3.45eV)和TiO2薄膜的禁带宽度(3.22eV),具有可见光响应能力.同时,K2Ti6O13薄膜电极的导带电位(-0.77V,vs.NHE)低于TiO2薄膜电极(-0.61V,vs.NHE),显示其还原能力优于TiO2薄膜电极,具有较强的光解水产氢潜力.此外,K2Ti6O13薄膜的电化学表征还表明其具有很好的电子-空穴分离能力和材料稳定性.因此,制备的K2Ti6O13薄膜在可见光光解水制氢领域将有较好的应用潜力.The sol-gel method was used to prepare potassium hexatitanate and titania thin films on indium-tin oxide （ITO） substrate by dip-coating. With this method, the connection between K2Ti6O13 film and ITO glass substrate was strong and maintained a good electrical contact. Electrochemical method combined with ultraviolet-visible light absorption spectrometry was used to ascertain the electronic band structure of K2Ti6O13 film. TiO2 film was used to verify the feasibility of this method and compared with K2Ti6O13 film as a reference system of structure and performance characteristic. The results show that the band gap energy of K2Ti6O13 film electrode estimated from the ultraviolet spectrum was 3.05 eV which is lower than that of K2Ti6O13 particle （3.45 eV） and TiO2 film （3.22 eV）. K2Ti6O13 film possessed visible light response capability. The lower edge of the conduction band of the potassium hexatitanate was approximately -0.77 V （vs. NHE） lower than that of anatase （-0.61 V vs. NHE）, which indicates that K2Ti6O13 film electrode possesses stronger reducibility. The potassium hexatitanate had the feasibility of hydrogen production from water photolysis. The electrochemical measurement also reveals that K2Ti6O13 is a stable photocatalyst with effective separation of photogenerated charge carriers. Consequently, the K2Ti6O13 film is a promising material in the field of hydrogen manufacturing with visible light.

关 键 词：六钛酸钾薄膜 光解水 氢能 能带结构 

分 类 号：O64[理学—物理化学]