Adaptive Amphiphilic Molecular Switch for Coordinated Spin-State and Interfacial Water Regulation Enables Fast Reconstruction for Efficient Oxygen Evolution

Abstract Sluggish catalyst reconstruction limits the oxygen evolution reaction (OER), in part because electronic-state regulation and interfacial mass transport are difficult to coordinate. Here, we establish an entropy–energy competition ratio (ξ = TΔS/ΔE, where T is the absolute temperature, ΔS is the spin-transition entropy change, and ΔE is the spin-transition energy barrier) as a quantitative descriptor for predicting amphiphile-mediated spin-state regulation. Its predictive capability is validated across amphiphiles with systematically varied headgroups and tail lengths. Guided by this descriptor, sodium dodecyl sulfate (SDS) functions as a potential-responsive molecular switch that couples headgroup-mediated stabilization of high-spin Co3+ with tail-mediated reorganization of interfacial water, thereby accelerating electrochemical reconstruction. The optimized catalyst requires an overpotential of 227 mV at 10 mA cm-2 and maintains stable operation for over 3000 h, while the design strategy is extendable across different catalyst systems. These findings establish a descriptor-guided molecular design framework for coordinating electronic and interfacial regulation in reconstruction-driven electrocatalysis.