Highly Selective Photocatalytic Conversion of Carbon Dioxide by Water over Al-SrTiO<sub>3</sub> Photocatalyst Modified with Silver–Metal Dual Cocatalysts
Shuying Wang, Kentaro Teramura, Takashi Hisatomi, Kazunari Domen, Hiroyuki Asakura, Saburo Hosokawa, Tsunehiro Tanaka
Abstract
In this study, an anisotropic facet-exposed Al-SrTiO3 photocatalyst modified with various Ag–metal (Fe, Co, Ni, and Pt) dual cocatalysts was investigated to elucidate the functions of the Ag and metals in the photocatalytic conversion of CO2 by H2O. The various dual cocatalysts were loaded on the surface of Al-SrTiO3 using a simultaneous photodeposition method. In particular, the modification of the FeOOH and metallic Ag cocatalysts on the surface of the Al-SrTiO3 photocatalyst markedly enhanced the CO formation rate (38.2 μmol h–1), with extremely high selectivity toward CO evolution (99.3%), during the photocatalytic conversion of CO2 by H2O under a relatively long light wavelength (λ ≥ 300 nm). In addition, the metallic Ag and FeOOH dual cocatalysts present on the surface of Al-SrTiO3 were durable and stable during the photoirradiated reaction, wherein the Ag and Fe deposited on the {100} and {110} facets functioned as active sites for the reduction of CO2 and oxidation of H2O, respectively.