Integrating Microenvironment Tailoring into Molecular Electrocatalysis

The emphasis put on the effects of the interfacial microenvironment in heterogeneous electrocatalysis has not been met in homogeneous molecular electrocatalysis. While it is widely recognized that the microenvironment governs activity, selectivity, and stability in heterogeneous systems, the catalytic behavior of the molecular catalysts has traditionally been interpreted using simplified mechanistic models that largely neglect the role of the electrode/electrolyte interface. Emerging yet limited evidence on both homogeneous and heterogenized molecular catalysts reveals that the reaction energetics and reactant availability through comprehensive electrolyte and electrode engineering can profoundly impact catalytic pathways, suppress competing reactions, and stabilize key intermediates. Consideration of the hydrophobicity, solvent and reactant availability, proton activity, electrolyte composition, and local electric field at the interfacial microenvironment may significantly enhance the electrocatalytic performance of molecular catalysts. This opinion presents a comparative perspective, highlighting how microenvironment-based concepts can provide valuable insight for understanding and designing next-generation molecular electrocatalytic systems.