Synergistic Tuning of Heterovalent States and Oxygen-Vacancy Defect Engineering in Hydrophilic W-Doped Sb 2 OS 2 for Enhanced Nitrogen Photoreduction to Ammonia

作者：Binghong Wu, Baoqian Yang, Xinru Wu, Dong–Hau Kuo, Zhengjie Su, Longyan Chen, Pengkun Zhang, Mengistu Tadesse Mosisa, Dongfang Lu, Zhanhui Yuan, Jinguo Lin, Xiaoyun Chen · 发表于：ACS Applied Materials & Interfaces · 年份：2024 · DOI：10.1021/acsami.4c16630 · 被引用次数：38 · 研究领域：Advanced Photocatalysis Techniques、Ammonia Synthesis and Nitrogen Reduction、Catalytic Processes in Materials Science

Nitrogen fixation reaction via photocatalysis offers a green and promising strategy for renewable NH 3 synthesis, and catalysts with high-efficiency photocatalytic properties are essential to the process. Herein, we demonstrate a W-doped Sb 2 OS 2 bimetal oxysulfide catalyst (labeled as SbWOS) with abundant oxygen vacancies, heterovalent metal states, and hydrophilic surfaces for nitrogen photoreduction to ammonia. The SbWOS-3 with suitable W-doping exhibited excellent nitrogen fixation activity of 408.08 μmol·g –1 ·h –1 and an apparent quantum efficiency (AQE) of 1.88% at 420 nm and a solar-to-ammonia (STA) conversion efficiency of 0.082% in pure water under AM1.5G light irradiation. The W-doping not only transforms hydrophobic Sb 2 OS 2 into a hydrophilic catalyst, making it easier for H 2 O molecules adsorbed on the SbWOS surface and catalyzed into protons, but also endows the SbWOS catalyst with rich oxygen vacancies, acting as the active sites for trapping and activating the N 2 molecule, and for trapping and activating H 2 O to produce the protons for the N 2 photocatalytic reduction reaction. The hydrazine drives the SbWOS catalyst with the heterovalent metal states, which acts as the photogenerate electrons quickly hopping between W 5+ and W 6+ to transfer for the N 2 reduction reaction. This study provides a feasible scheme for applying oxygen vacancy defects, heterovalent metal states, and surface hydrophobic-to-hydrophilic wetting engineering in bimetal oxysulfide ...