Remote allosteric control of single-atom Cu sites in Zr-MOFs enables selective CH 4 hydroxylation

Highly selective oxidation of methane to liquid oxygenates under mild conditions remains challenging because of the difficulty in controlling overoxidation at highly reactive sites. Here, we demonstrate remote control of single-atom Cu reactivity through outer-shell coordination engineering in Zr-based metal-organic frameworks (MOFs). By anchoring Cu 1 to Zr-oxo nodes in UiO-66-X (X = -NO 2 , -H, and -CH 3 ), remote X-BDC ligands systematically modulate the electronic properties of Cu 1 sites and the catalytic microenvironment. In situ characterization combined with ab initio molecular dynamics in an explicitly solvated aqueous environment reveals a dynamic outer-shell-to-inner-shell regulation that reshapes the active structure and reactive oxygen species around Cu 1 sites, thereby facilitating CH 4 activation. In particular, the electron-withdrawing NO 2 -BDC ligand creates electron-deficient Cu 1 - • OH* sites, while adsorbed water further regulates active-site conformation. Consequently, Cu 1 /U6-NO 2 achieves a turnover frequency of 322.4 h −1 with nearly 100% oxygenate selectivity under mild conditions, establishing a general strategy for overcoming activity-selectivity trade-offs in methane conversion.