An in situ FT-IR Study on Photocatalytic Reaction at Semiconductor-Aqueous Solution Interface — Mechanism of Photocatalytic N-Cyclization of (S)-Lysine

Photoinduced reaction occurring at an aqueous solution-semiconductor interface was analyzed in situ by reflection FT-IR spectroscopy. The photoinduced reflection spectral change, ΔR (= (R−R0)/R0), was recorded by using an IR cell consisting of a semiconductor (TiO2 or CdS) thin film electrode, a thin layer of aqueous (S)-lysine solution, and a calcium fluoride window. Structure of adsorbed substrate and mechanism of photoinduced reaction were discussed.