Metal-phenolic networks improve interfacial electron transfer in bio-electrochemical systems

Multi-enzyme electrocatalytic cascades often suffer from poor electron-transfer efficiency, limiting their utility. We overcome this critical challenge by integrating an interfacial metal–phenolic network (MPN) layer with tunable properties based on the metal and polyphenol employed. Upon electropolymerization, MPNs provide a stable matrix for co-immobilizing glucose oxidase and horseradish peroxidase, enhancing their tandem activity. Through systematic evaluation of the impact of MPN composition on electron transfer, we demonstrate the tunability of these materials for cascade-specific optimization. This simple material is expected to support diverse enzymatic reactions important for technologies ranging from bioenergy to biosensing.