Broadening the Action Spectrum of TiO-Based Photocatalysts to Visible Region by Substituting Platinum with Copper.

In this study, TiO-based photocatalysts modified with Pt and Cu/CuO were synthesized and studied in the photocatalytic reduction of CO. The morphology and chemical states of synthesized photocatalysts were studied using UV-Vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. A series of light-emitting diodes (LEDs) with maximum intensity in the range of 365-450 nm was used to determine the action spectrum of photocatalysts. It is shown for, the first time, that the pre-calcination of TiO at 700 °C and the use of Cu/CuO instead of Pt allow one to design a highly efficient photocatalyst for CO transformation shifting the working range to the visible light (425 nm). Cu/CuO/TiO (calcined at 700 °C) shows a rate of CH formation of 1.2 ± 0.1 µmol h g and an overall CO reduction rate of 11 ± 1 µmol h g (at 425 nm).