Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO2 Reduction

Highlights The S-vacancies result in the change of d-band electronic state of Mo. An internal quantum efficiency of 94.01% at 380 nm for photocatalytic CO 2 reduction reaction (CO 2 RR). The Mo–S bridging bonds optimize adsorption energies and accelerate CO 2 RR kinetics. We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO 2 reduction reaction (CO 2 RR) via Mo – S bridging bonds sites in S v –In 2 S 3 @2H–MoTe 2 . The X-ray absorption near-edge structure shows that the formation of S v –In 2 S 3 @2H–MoTe 2 adjusts the coordination environment via interface engineering and forms Mo – S polarized sites at the interface. The interfacial dynamics and catalytic behavior are clearly revealed by ultrafast femtosecond transient absorption, time-resolved, and in situ diffuse reflectance–Infrared Fourier transform spectroscopy. A tunable electronic structure through steric interaction of Mo – S bridging bonds induces a 1.7-fold enhancement in S v –In 2 S 3 @2H–MoTe 2 (5) photogenerated carrier concentration relative to pristine S v –In 2 S 3 . Benefiting from lower carrier transport activation energy, an internal quantum efficiency of 94.01% at 380 nm was used for photocatalytic CO 2 RR. This study proposes a new strategy to design photocatalyst through bridging sites to adjust the selectivity of photocatalytic CO 2 RR.