Porphyrinic MOF derived Single-atom electrocatalyst enables methanol oxidation

Abstract

Electrochemical methanol oxidation reaction (MOR) serves as a key route for renewable energy technologies. However, unmet challenges remain in the preparation of low-cost, efficient and robust electrocatalysts for MOR. Herein, a porphyrinic metal–organic framework (MOF) with spatially isolated Ni centres is prepared. Upon pyrolysis, this affords a single-atom Ni implanted nitrogen-doped porous carbon (20% Ni-N-C). Integrating abundant and accessible single-atom Ni sites, hierarchical porosity, excellent conductivity with stable Ni-N4 moieties all in one, the derived ultra-stable 20% Ni-N-C exhibits high MOR activity, impressive durability and CO tolerance, thereby outperforming state-of-the-art nonprecious metal based electrocatalysts. Computational insights reveal a low energy barrier of 1.19 eV for the rate-determining step, in agreement with the experimental observations of superior MOR activity. As the first foray into improving MOR efficiency with nonprecious metal based single-atom electrocatalysts, the yet-unrealized potential for MOFs and related modular hybrids is demonstrated.