Photoelectrochemical Reduction of Carbon Dioxide at Si(III) Electrode Modified by Viologen Molecular Layer with Metal Complex

摘要

Photoelectrochemical carbon dioxide reduction was carried out at a p-type Si(III) electrode modified with a viologen molecular layer and [AuCl4]~- or [PdCl4]~(2-). It was proven that the reduction reaction was mediated by viologen moiety and while CO2 reduction was dominant at the Si(111) electrode modified with [PdCl4]~(2-) in the potential region where viologen moiety was in the first reduced state, it became dominant at the electrode modified with [AuCl4]~- when viologen moiety became the second reduced state. FT-IR measurement confirmed the formation of formic acid/formate ion at the [PdCl4]~(2-)/viologen-modified Si electrode.