Integrating salen complexes into gas diffusion electrodes for CO2 electroreduction: considerations for employing molecular precatalysts in heterogeneous electrolyzers

Transition metal salen complexes (Co, Ni, Cu) are studied as precatalysts for CO2-to-CO electroreduction in zero-gap electrolyzers. Performance depends strongly on metal choice and electrode characteristics. XPS, UV-Vis, comparisons to simple metal salts, and a RHE-ZGE half-cell setup shed light on precatalyst decomposition and inform methodologies for molecular electrocatalyst heterogenization.