Z-scheme heterojunction Zn3(OH)2(V2O7)(H2O)2/V-Zn(O,S) for enhanced visible-light photocatalytic N2 fixation via synergistic heterovalent vanadium states and oxygen vacancy defects

作者：Pengkun Zhang, Qinhan Wu, Haoyu Wang, Dong–Hau Kuo, Yujie Lai, Dongfang Lu, Jiqing Li, Jinguo Lin, Zhanhui Yuan, Xiaoyun Chen · 发表于：CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION) · 年份：2025 · DOI：10.1016/s1872-2067(25)64716-4 · 被引用次数：49 · 研究领域：Advanced Photocatalysis Techniques、Advanced Nanomaterials in Catalysis、Copper-based nanomaterials and applications

Herein, we established a Zn 3 (OH) 2 (V 2 O 7 )(H 2 O) 2 /V-Zn(O,S) Z-scheme heterojunction (labeled ZnVO/V-Zn(O,S) with a heterovalent V 4+ /V 5+ states and oxygen vacancies in both phases via a one-step in-situ hydrolysis method. The NaBH 4 regulated the ZnVO/V-Zn(O,S)-3 with rich Vo and suitable n (V 4+ )/ n (V 5+ ) ratio achieved an excellent photocatalytic nitrogen fixation activity of 301.7 μmol/(g·h) and apparent quantum efficiency of 1.148% at 420 nm without any sacrificial agent, which is 11 times than that of V-Zn(O,S). The Vo acts as the active site to trap and activate N 2 molecules and to trap and activate H 2 O to produce the H for N 2 molecules photocatalytic reduction. The rich Vo defects can also reduce the competitive adsorption of H 2 O and N 2 molecules on the surface active site of the catalyst. The heterovalent vanadium states act as the photogenerated electrons, quickly hopping between V 4+ and V 5+ to transfer for the photocatalytic N 2 reduction reaction. Additionally, the Z-scheme heterojunction effectively minimizes photogenerated carrier recombination. These synergistic effects collectively boost the photocatalytic nitrogen fixation activity. This study provides a practical method for designing Z-scheme heterojunctions for efficient photocatalytic N 2 fixation under mild conditions.