Ru/H MoO3- with plasmonic effect for boosting photothermal catalytic CO2 methanation

Utilizing localized surface plasmon resonance (LSPR) effect of catalysts to facilitate photothermal catalysis of CO2 to CH4 is an attractive strategy for mitigating CO2 emissions. Herein, we demonstrate that Ru/HxMoO3-y synthesized via H-spillover exhibits plasmonic absorption in the visible-near-infrared (Vis-NIR) region, achieving a CH4 yield of 20.8 mmol/gcat/h (520 mmol/gRu/h) with 100 % selectivity in the CO2 methanation under Vis-NIR light irradiation at 140 °C. Irradiation with Vis-NIR light substantialy increases the CH4 yield (~ 4.7 fold) compared with that under dark conditions. The abundant surface oxygen vacancies provide active sites for CO2 adsorption and activation. In situ infrared spectroscopic analysis reveals that photothermal catalytic CO2 methanation follows *CO pathway. This work represents a simple strategy for developing a plasmonic catalyst for efficient photothermal catalytic CO2 methanation.