Electrocatalytic Hydrogenation with MOF-derived Cobalt Nanoparticles

Electrochemical hydrogenation (e-H) of organic substrates represents a key transformation for advancing industrial electrification and sustainable chemical manufacturing. Here, we represent e-H of acetone and pyridine by cobalt nanoparticles derived from a Co-based MOF. A novel two-dimensional cobalt metal–organic framework, Co-L0-NS, featuring a kgd-type layered topology with Co(II) paddlewheel nodes and polyaromatic linkers, has been synthe-sized and structurally characterized. Electrochemical reduction of Co-L0-NS induces controlled framework recon-struction, producing highly dispersed cobalt nanoparticles that efficiently catalyze the e-H of acetone to isopropanol and show moderate activity toward pyridine reduction to piperidine. In contrast, electrodeposition from aqueous Co²⁺ precursors forms larger, more crystalline metallic Co particles. Spectroscopic and electrochemical analyses, sup-ported by Tafel modeling, indicate a proton-coupled electron-transfer (PCET) mechanism with a rate-determining step exhibiting a Tafel slope of ~150 mV dec⁻¹. These findings highlight how structural features of the parent MOF—open Co sites, two-dimensional connectivity, and redox flexibility—govern nanoparticle formation and catalytic be-havior, providing design principles for MOF-derived cobalt electrocatalysts.