Second Coordination Sphere-Regulated Nickel Sites Enable Enhanced Photocatalytic Eight-Electron Reduction of Carbon Dioxide to Methane

作者：Mengyang Zhang, Cui Xu, Qiang Gao, Teng Li, Kefan Zhang, Suwen Wang, Xianjun Yin, Hui‐Qing Peng, Junye Cheng, Zenghe Li, Bin Liu · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.5c03244 · 被引用次数：4 · 研究领域：CO2 Reduction Techniques and Catalysts、Advanced Photocatalysis Techniques、Covalent Organic Framework Applications

The photocatalytic eight-electron reduction of CO 2 to CH 4 holds great promise for fuel production but suffers from sluggish kinetics and poor selectivity due to intricate multiproton/electron transfer. Herein, we report an atomic-scale regulation of nickel sites via constructing a multifunctional second coordination sphere (SCS) by leveraging Fe 3+ -mediated supramolecular assembly with a metalloporphyrin regulator, dramatically boosting CH 4 generation. Specifically, the SCS-tailored catalyst achieves a high CH 4 production rate of 420.3 μmol·g –1 ·h –1 with 91.0% selectivity and suppresses H 2 evolution, significantly surpassing the pristine counterpart and ranking among the most efficient systems reported thus far. Fine structural characterizations reveal that SCS, constructed through electrostatic interaction and hydrogen bonding, induces lattice compression and generates lower-valence Ni δ+ sites. In situ XAFS, in situ FTIR, and density functional theory calculations demonstrate that the SCS strengthens CO 2 binding, stabilizes *CO for protonation, and reduces energy barriers for *COOH formation, thus leading to the significantly enhanced CH 4 activity. In addition, SCS-mediated electronic modulation optimizes the conduction band position, enhancing charge separation and transfer efficiency to synergistically accelerate the CO 2 -to-CH 4 conversion. This work establishes an SCS engineering paradigm to atomically master complex multielectron photoreductions, offering a ...