A photoelectrochemical device with a nanostructured SnO2 electrode modified with composite clusters of porphyrin-modified silica nanoparticle and fullerene.
A silica nanoparticle has been successfully employed as a nanoscaffold to self-organize porphyrin and C60 molecules on a nanostructured SnO2 electrode. The quenching of the porphyrin excited singlet state on the silica nanoparticle is suppressed significantly, showing that silica nanoparticles are promising scaffolds for organizing photoactive molecules three-dimensionally in nanometer scale. Marked enhancement of the photocurrent generation was achieved in the present system compared with the reference system, where a gold core was employed as a scaffold of porphyrins instead of a silica nanoparticle. The rather small incident photon-to-current efficiency relative to a similar photoelectrochemical device using a silica microparticle may result from poor electron and hole mobility in the composite film due to poor connection between the composite clusters of a porphyrin-modified silica nanoparticle and C60 in micrometer scale.
Imahori
Hiroshi
H
Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan. imahori@scl.kyoto-u.ac.jp
Mitamura
Keigo
K
Shibano
Yuki
Y
Umeyama
Tomokazu
T
Matano
Yoshihiro
Y
Yoshida
Kaname
K
Isoda
Seiji
S
Araki
Yasuyuki
Y
Ito
Osamu
O