CuOx supported LaCoO3 perovskite for the photoassisted reverse water gas shift reaction at low temperature

Abstract

CuOx/LaCoO₃ systems have been studied for the rWGS reaction under thermal assisted photocatalytic conditions within low temperature range of 180–330 ºC. CuOx species deposited from chemical reduction method over LaCoO₃ homogeneously covered the perovskite surface. The reduction pretreatment before reaction leads to the partial Co reduction and the complete reduction of Cu. A significant improvement on CO production has been attained upon Cu incorporation. In addition, upon UV–vis irradiation the CO production is also enhanced. Best results have been obtained for 5 wt% Cu. The highest synergistic effect was observed for the lowest temperature, for which catalytic contribution is negligible. Thus, a good compromise is attained at 300 ºC for which a CO production of 5.45 mmol/h·g and 92 % selectivity, showing a good synergistic effect between thermo and thermo-photocatalytic activity.