Directed Amorphous-to-Amorphous Reconstruction Toward Efficient Oxygen Evolution

To fully unlock catalytic potential in the oxygen evolution reaction (OER), it is essential to guide the reconstruction process, orienting the evolution from the initial amorphous state into a more potent amorphous structure. We develop an amorphous cobalt coordination polymer (aCo) pre-catalyst via monodentate end-capping. In-situ synchrotron radiation X-ray diffraction reveals that CH₃CN coordination disrupts the long-range topological order while preserving local motifs. The obtained metastable amorphous structure redirect spontaneous surface reconstruction into an amorphous cobalt oxyhydroxide (a-CoOOH) active layer due to strong d-π* interactions with the lower energetic barrier (-8.175 eV) compared to the crystalline phase on its counterpart (-7.441 eV). The unique amorphous-to-amorphous transformation effectively activates lattice oxygen within the metastable framework, switching the OER pathways from the adsorbate evolution mechanism to a lattice oxygen-mediated mechanism and consequently enhancing OER efficiency and stability. The optimized amorphous aCo can achieve an overpotential of 186 mV at 10 mA cm^-2, much lower than those of RuO₂ (233 mV) and crystalline cCo (308 mV), and it demonstrates stability of over 100 h at 2 A cm^-2. This strategy offers a directed surface-induced approach for designing next-generation OER electrocatalysts, providing fundamental insights into the correlation between lattice oxygen activity and structural long-range disorder.