Maleimide-Functionalized Conjugated Polymers Enable Covalent Biotic-Abiotic Integration to Boost Microbial Electrosynthesis

Integrating advanced conductive materials into microbial electrosynthesis systems is a powerful paradigm for merging abiotic performance with biotic specificity, facilitating sustainable transformation of organic waste and carbon dioxide into value-added chemicals. The regulation of biotic-abiotic hybrid interfaces in biohybrids is crucial for improving surface microbial abundance, enhancing electron injection, and increasing electrosynthesis production. Herein, maleimide-functionalized conjugated polymers (p(mNDI-gT2)) were employed to construct robust, covalent bio-interfaces via in situ click reactions with cytochrome thiol groups of Shewanella oneidensis, resulting in a doubling of bacterial adhesion. Moreover, intimate contact and binding interactions drastically reduce interfacial resistance and boost electron injection. As a direct consequence of this optimized architecture, the system achieved a 23-fold increase in electron transfer and a 6-fold improvement in electrochemical reduction relative to bare S. oneidensis. Furthermore, it obviously outperformed the non-covalent group, yielding a 2-fold enhancement in total charge output and a 2-fold increase in succinate yield. Molecular docking simulations and proteomic analysis collectively reveal that p(mNDI-gT2) not only facilitates efficient charge transfer but also predominantly upregulates the expression of key respiratory and bio-interface protein complexes. Fundamentally, this covalent biotic-abiotic interface transcends traditional bulk-adsorption methods, shifting the paradigm from simple microbial coating to molecular-level interface engineering.