Interfacial electric polarization in biohybrid catalysis.

Biohybrid catalysis, which couples renewable energy conversion with biological metabolism, offers a promising route for the sustainable production of value-added chemicals and fuels. However, the physicochemical principles governing electron transfer and energetic coupling across microbe-material interfaces remain poorly understood, partly because interfacial charge redistribution and local electric fields that shape electron-transfer energetics are difficult to characterize and quantify. Here, we propose interfacial electric polarization as a conceptual framework for understanding how localized electric fields and charge redistribution reshape interfacial energetics and influence electron-transfer pathways and catalytic function at microbe-material interfaces. We discuss how electric polarization may shape interfacial electron transfer through three interconnected concepts: energetic asymmetry, energetic matching, and dynamic electric polarization. Finally, we highlight challenges in characterizing interfacial energetic states, understanding microbial responses to polarized environments, developing quantitative energetic descriptors, and establishing predictive models for interface engineering. We anticipate that advances in operando characterization, multiscale modeling, and electric polarization-responsive materials will enable quantitative evaluation of interfacial energetic states and establish interfacial electric polarization as a design principle for predictive and high-performance biohybrid catalytic systems.