Preparation of Carbon-Coated Titanium Oxides and Their Photocatalytic Activity

Abstract
Carbon coating of titanium oxide (TiO2) powders was successfully performed by heating a mixture of anatase-type TiO2 with poly (vinyl alcohol) at different temperatures above 700°C in an inert atmosphere. Photocatalytic activity was examined by measuring color fading of methylene blue (MB) aqueous solution under UV irradiation. The carbon coating was found to stabilize the anatase structure up to 800°C. Carbon-coated anatase powders showed comparable photoactivity for MB decomposition to the original anatase powder without carbon coating, even better in some cases. Carbon-coated anatase powders were found to have a high adsorptivity mainly due to carbon layer.