Construction of Core-shell Sb₂ s₃ @Cds Nanorod with Enhanced Heterointerface Interaction for Chromium-Containing...

How to collaboratively reduce Cr(VI) and break Cr(III) complexes is a technical challenge to solve chromium-containing wastewater (CCW) pollution. Solar photovoltaic (SPV) technology based on semiconductor materials is a potential strategy to solve this issue. Sb₂ S₃ is a typical semiconductor material with total visible-light harvesting capacity, but its large-sized structure highly aggravates disordered photoexciton migration, accelerating the recombination kinetics and resulting low-efficient photon utilization. Herein, the uniform mesoporous CdS shell is in situ formed on the surface of Sb₂ S₃ nanorods (NRs) to construct the core-shell Sb₂ S₃ @CdS heterojunction with high BET surface area and excellent near-infrared light harvesting capacity via a surface cationic displacement strategy, and density functional theory thermodynamically explains the breaking of SbS bonds and formation of CdS bonds according to the bond energy calculation. The SbSCd bonding interaction and van der Waals force significantly enhance the stability and synergy of Sb₂ S₃ /CdS heterointerface throughout the entire surface of Sb₂ S₃ NRs, promoting the Sb₂ S₃ -to-CdS electron transfer due to the formation of built-in electric field. Therefore, the optimized Sb₂ S₃ @CdS catalyst achieves highly enhanced simulated sunlight-driven Cr(VI) reduction (0.154 min^-1 ) and decomplexation of complexed Cr(III) in weakly acidic condition, resulting effective CCW treatment under co-action of photoexcited electrons and active radicals. This study provides a high-performance heterostructured catalyst for effective CCW treatment by SPV technology.