Kozo Inoue

Spectroscopic and photoelectrochemical differences between racemic and enantiomeric [Ru(phen)3]2+ ions intercalated into layered niobate K4Nb6O17

Abstract Chirality effects have been observed in the intercalation, spectroscopic and photoelectrochemical behavior when enantiomeric and racemic [Ru(phen) 3 ] 2+ complexes were intercalated in the interlayer spaces of K 4 Nb 6 O 17 . The results were interpreted in terms of a [Nb 6 O 17 ] 4− -chelate and chelate–chelate interactions. The faster luminescence decay and higher photocurrent of the enantiomeric [Ru(phen) 3 ] 2+ –K 4 Nb 6 O 17 compounds than the racemic ones suggest that the emission of adsorbed [Ru(phen) 3 ] 2+ ions was not only quenched by adsorbed complexes (or concentration quenching) but also by the semiconductive host lattices.

Fabrication and photoelectrochemical characterization of CdS particles in nanospaces of expandable mica

Abstract Photoelectrochemical properties are investigated for CdS nanoparticles formed in a solution as well as in the nanospaces of expandable mica (EM). The smallest sized CdS particles (≈3 nm in diameter) were obtained in the nanospaces of Cd 2+ exchanged EM (1.2 μm in crystal size) by reacting with H 2 S in the absence of interlayer water. The existence of interlayer water was found to influence the size of CdS particles remarkably. Smaller EM crystals limited the particle growth of CdS along the sheets. Photocurrent was measured for the CdS-EM suspensions/methylviologen system and the CdS-EM film electrode. The variation of the steady state photocurrent value ( i ss ) with pH, showed that i ss increased with the decrease of CdS particle size, while the intersection point (termed as pH 0 ) showed a negative shift with the decrease of CdS particle size. The action spectrum of the CdS-EM film electrode was in good agreement with their absorption spectra of the suspension.