Molecular-level insight into photocatalytic CO2 reduction with H2O over Au nanoparticles by interband transitions

Abstract Achieving CO 2 reduction with H 2 O on metal photocatalysts and understanding the corresponding mechanisms at the molecular level are challenging. Herein, we report that quantum-sized Au nanoparticles can photocatalytically reduce CO 2 to CO with the help of H 2 O by electron-hole pairs mainly originating from interband transitions. Notably, the Au photocatalyst shows a CO production rate of 4.73 mmol g −1 h −1 (~100% selectivity), ~2.5 times the rate during CO 2 reduction with H 2 under the same experimental conditions, under low-intensity irradiation at 420 nm. Theoretical and experimental studies reveal that the increased activity is induced by surface Au–O species formed from H 2 O decomposition,…

• NN
  National Natural Science Foundation of China

  Awards: 21831003, 21972082, 21673220
• PG
  People's Government of Jilin Province
• DO
  Department of Science and Technology of Jilin Province

  Award: 20200201001JC