Photoelectric Properties Based on Electric Field Modulation of Photoinduced Electron Transfer Processes in Flavin-Porphyrin Hetero-type Langmuir–Blodgett Films

Autor: Satoshi Nishikawa, Satoru Isoda, Kouich Akiyama, Yoshio Hanazato, Satoshi Ueyama
Rok vydání: 2004
Předmět:
Zdroj: Japanese Journal of Applied Physics. 43:2774
ISSN: 1347-4065
0021-4922
DOI: 10.1143/jjap.43.2774
Popis: Metal–insulator–meal devices composed of flavin-porphyrin hetero-type Langmuir–Blodgett films showed highly efficient photoelectric properties mainly attributable to the fast charge separation process at a molecular heterojunction (MHJ) between flavin and porphyrin. The photoelectric properties of the MHJ devices showed different characteristics depending on the redox state of the central metal of porphyrin, i.e., Ru(III) or Ru(II). The rectifying behavior of the photocurrent was observed for the Ru(III)-MHJ device, whereas the Ru(II)-MHJ device did not show the rectifying behavior. We concluded that the rectifying behavior was mainly controlled by the electric field dependence of the charge recombination process. Furthermore, a bell-shaped photocurrent-voltage curve was observed for the Ru(II)-MHJ device. The mechanism underlying the negative resistance might be based on the electric field dependence of the charge shift process in flavin monolayers controlled by the inverted region mechanism of the Marcus electron transfer theory.
Databáze: OpenAIRE