MOF‐Derived Sulfur‐Doped NiO/NiS Heterostructures With Schottky‐Junction‐Assisted Charge Transfer for Selective Photocatalytic CO 2 Methanation
Haiyan Wang, Hongli Yang, Caili Li, Sijie Chen, Yuqing Jiang, Xumeng Yang, Xiaoqiang Zhan, Dongdong Zhang, Shaoyi Wang, Huilin Hou, Weiyou YangABSTRACT
A metal–organic framework (MOF)‐derived sulfur‐doped NiO/NiS heterostructure was constructed for selective photocatalytic CO 2 methanation by coupling sulfur‐induced electronic modulation with interfacial charge transfer. High‐resolution transmission electron microscopy (HRTEM) reveals an intimate S‐NiO/NiS heterointerface, while ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) shows enhanced visible‐light absorption and bandgap narrowing from 3.14 to 3.00 eV. The optimized NiOS‐15 achieves a CH 4 production rate of 13.41 µmol·g −1 ·h −1 , which is 5.94 times that of pristine NiO, together with a CH 4 selectivity of 92.12%. Work‐function calculations reveal interfacial electron redistribution and Schottky‐junction‐assisted charge transfer. In situ irradiation x‐ray photoelectron spectroscopy (XPS) further verifies directional photoinduced charge redistribution, while in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) identifies key intermediates involved in CO 2 ‐to‐CH 4 conversion. This work integrates MOF‐derived porous architecture, sulfur‐induced electronic regulation, and S‐NiO/NiS interfacial engineering for efficient and selective CO 2 methanation.