Single‐Atom Cu Anchoring on Heterocyclic Ring of Metal‐Organic Frameworks for Photocatalytic Nitrogen Fixation

Abstract Photocatalytic nitrogen fixation is a promising method for solving energy crisis and environmental problems. In this study, a straightforward approach to synthesize a single‐atom catalyst CZ‐1.5. The catalyst is developed through the formation of covalent bonds between copper atoms and a metal‐organic framework (MOF). The experimental data have demonstrated that Cu binds to the MOF through the N on the ligand and the defect sites on the Zr oxide cluster. The CZ‐1.5 shows the best nitrogen photofixation performance under ambient conditions and reaches 199.30 µmol g⁻¹ h⁻¹, which is 1.47 times than that of Zr‐MOF. Density functional theory calculation combined with X‐ray Absorption Fine Structure results reveal the possible hydrogenation pathway of single‐atom active site. This work provides a new approach for the design of non‐precious‐metal single‐atom photocatalysts that single atoms are bound to organic ligands and oxidation cluster defects of MOFs, which contribute to the advancement of sustainable development.