摘要
应用光电化学方法研究了N,N'-对羧苄基吲哚三菁(Cy5)染料敏化TiO2纳米晶电极的光电化学行为,优化了敏化的条件.结合Cy5的循环伏安曲线和光吸收阈值,初步确定Cy5电子基态和激发态能级位置.结果表明,Cy5电子激发态能级位置能与TiO2纳米粒子导带边位置相匹配,因而使用该染料敏化可以显著提高TiO2纳米晶的光电流,使TiO2纳米晶电极吸收波长由紫外光区红移至可见光区和近红外区,光电转换效率得到明显改善,在膜厚为6.5μm、敏化时间为6h的条件下IPCE值(incidentphoto-to-electricityconversionefficiency)最高可达46.4%,总的光电转换效率η为1.70%.
The photoelectrochemical behaviors of the TiO2 nanocrystalline electrode sensitized by Cy5 (N-carboxylbenzyl-3, 3-dimethyl-3 H-indole squarylium cyanine dye) were reported. The sensitized conditions were optimized. The ground state level and the excited state level of the dye were determined by using the cyclic voltammetry and the optical absorption spectroscopy. The results show that the excited state level of this dye matches the conduction band edge of TiO2 nanoparticles. Therefore the sensitization of the dye can obviously increase the photocurrent density of TiO2 nanocrystalline electrode and results in a red-shift of optical absorption from the ultra-violet region to the visible and near infra-red region. As a result, the light-to-electricity conversion efficiency was greatly improved and the maximum value of IPCE reached 46.4% and eta was 1.70% when the TiO2 nanostructured porous film was 6.5 mum thick and was sensitized for 6 h.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2004年第8期849-853,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(20073003)资助项目~~
