Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO2 Reduction

Abstract

We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO₂ reduction reaction (CO₂RR) via Mo-S bridging bonds sites in S_v-In₂S₃@2H-MoTe₂. The X-ray absorption near-edge structure shows that the formation of S_v-In₂S₃@2H-MoTe₂ 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-In₂S₃@2H-MoTe₂(5) photogenerated carrier concentration relative to pristine S_v-In₂S₃. Benefiting from lower carrier transport activation energy, an internal quantum efficiency of 94.01% at 380 nm was used for photocatalytic CO₂RR. This study proposes a new strategy to design photocatalyst through bridging sites to adjust the selectivity of photocatalytic CO₂RR.

Keywords: Bridging sites; CO2 reduction; Electronic structure; Quantum efficiency; Steric interaction.