Electrochemical investigation of traps in a nanostructured TiO2 film

被引：171

作者：

Wang, HL ^{[1
]}

He, JJ ^{[1
]}

Boschloo, G ^{[1
]}

Lindström, H ^{[1
]}

Hagfeldt, A ^{[1
]}

Lindquist, SE ^{[1
]}

机构：

[1] Univ Uppsala, Dept Chem Phys, S-75121 Uppsala, Sweden

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2001年 / 105卷 / 13期

关键词：

D O I：

10.1021/jp0036083

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Electron traps at the nanostructured TiO2 (anatase)/aqueous electrolyte interface have been studied by means of electrochemical methods. The transient current decays at different potentials positive of the flat band potential clearly illustrate the trap-filling process. The more negative the potential, the shorter the trap-filling period. It is found that most traps locate positive of -0.9 V vs Ag/AgCl at pH 13, or positive of -0.3 V vs Ag/AgCl at pH 4.7. It is proposed that the trap distribution as a function of potential is directly proportional to dQ/dU, i.e., to the current density in a linear sweep voltammetry experiment. The trap densities in aqueous electrolytes are estimated to be 4 x 10(11) cm(-2) (microscopic area) at pH 4.7 and 5 x 10(13) cm(-2) (microscopic area) at pH 13. The pH dependency of the trap density indicates that traps investigated are surface-related.

引用

页码：2529 / 2533

页数：5

共 30 条

[1] PREPARATION AND PHOTOELECTROCHEMICAL CHARACTERIZATION OF THIN SNO(2) NANOCRYSTALLINE SEMICONDUCTOR-FILMS AND THEIR SENSITIZATION WITH BIS(2,2'-BIPYRIDINE)(2,2'-BIPYRIDINE-4,4'-DICARBOXYLIC ACID)RUTHENIUM(II) COMPLEX [J].