Decoupling OH and H Binding via Dual-Site Conductive MOFs for Efficient Alkaline Hydrogen Evolution

Efficient regulation of the hydrogen and hydroxyl binding energies (HBE/OHBE) lies at the core of developing high-performance alkaline hydrogen evolution reaction (HER) electrocatalysts, yet it remains challenging due to the inherent correlation between the two binding energies. Herein, we demonstrate a d-electron modulation strategy on dual-metal sites to break the scaling constraint and synergistically optimize HBE and OHBE. A well-defined Cu-based two-dimensional conductive metal-organic framework (Cu-HHTP) serves as a universal host to incorporate various 3d transition metals (Mn, Fe, Co, Ni, Cu), yielding M-Cu dual sites with finely tunable d-electron configurations. Density functional theory calculations combined with experiments reveal that higher d-electron occupancy of the secondary metal site lowers the d-band center, and the water dissociation energy barrier exhibits a typical volcano-type trend. The Co-Cu dual sites at the volcano apex promote the Volmer step through optimized OHBE and water adsorption. Meanwhile, this dual-site configuration promotes the rearrangement of interfacial water molecules by disrupting the hydrogen-bond network, thereby optimizing HBE. This work decouples HBE and OHBE via d-electron configuration, shifting the design paradigm from empirical screening to predictive design.