Photo-Induced Switching of CO2 Hydrogenation Pathway towards CH3 OH Production over Pt@UiO-66-NH2 (Co)
Jianmin Chen1, Yajing Wang1,2, Fengliang Wang1
1School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
Abstract:
It is highly desired to achieve controllable product selectivity in CO2 hydrogenation. Herein, we report light-induced switching of reaction pathways of CO2 hydrogenation towards CH3 OH production over actomically dispersed Co decorated Pt@UiO-66-NH2 . CO, being the main product in the reverse water gas shift (RWGS) pathway under thermocatalysis condition, is switched to CH3 OH via the formate pathway with the assistance of light irradiation. Impressively, the space-time yield of CH3 OH in photo-assisted thermocatalysis (1916.3 μmol gcat -1 h-1 ) is about 7.8 times higher than that without light at 240 °C and 1.5 MPa. Mechanism investigation indicates that upon light irradiation, excited UiO-66-NH2 can transfer electrons to Pt nanoparticles and Co sites, which can efficiently catalyze the critical elementary steps (i.e., CO2 -to-*HCOO conversion), thus suppressing the RWGS pathway to achieve a high CH3 OH selectivity.
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