A green synthetic approach for C/Ag@ urchin-like TiO2 nanocomposites showing a highly molar ratio CH4/CO for CO2 photoreduction

Abstract

In the paper, the urchin-like TiO2 with rutile crystal structure was prepared under acidic conditions. When C powder was added in the reaction process, rutile TiO2 became rutile and anatase diphase structure. The yields of CH4 and CO of C/Ag@TiO2 were 5.46 μmol·g−1·h−1 and 1.51 μmol·g−1·h−1, respectively, and the molar ratio of CH4 was the highest for 78.3%. Through characterization of optical and electrical properties, the addition of C and Ag improved the optical performance, carrier concentration, and electron mobility. Finally, the photocatalytic reaction mechanism was proposed.