Enhanced CO evolution for photocatalytic conversion of CO2 by H2O over Ca modified Ga2O3
Rui Pang, Kentaro Teramura, Masashige Morishita, Hiroyuki Asakura, Saburo Hosokawa, Tsunehiro Tanaka
Abstract
Abstract Artificial photosynthesis is a desirable critical technology for the conversion of CO 2 and H 2 O, which are abundant raw materials, into fuels and chemical feedstocks. Similar to plant photosynthesis, artificial photosynthesis can produce CO, CH 3 OH, CH 4 , and preferably higher hydrocarbons from CO 2 using H 2 O as an electron donor and solar light. At present, only insufficient amounts of CO 2 -reduction products such as CO, CH 3 OH, and CH 4 have been obtained using such a photocatalytic and photoelectrochemical conversion process. Here, we demonstrate that photocatalytic CO 2 conversion with a Ag@Cr-decorated mixture of CaGa 4 O 7 -loaded Ga 2 O 3 and the CaO photocatalyst leads to a satisfactory CO formation rate (>835 µmol h −1 ) and excellent selectivity toward CO evolution (95%), with O 2 as the stoichiometric oxidation product of H 2 O. Our photocatalytic system can convert CO 2 gas into CO at >1% CO 2 conversion (>11531 ppm CO) at ambient temperatures and pressures.