Core Viewpoint - The article discusses the development of a spatially decoupled electro-biosystem for efficient CO2 conversion into valuable chemicals, highlighting the integration of electrochemical and microbial fermentation processes to enhance product yield and selectivity [4][13]. Summary by Sections CO2 Reduction Technology - CO2 electroreduction (CO2 RR) technology utilizes clean electricity to convert CO2 into high-value chemicals, addressing resource scarcity [3]. - Current advancements allow for efficient conversion of CO2 into C1-C2 products like carbon monoxide, methane, and ethanol, but challenges remain in synthesizing high-energy-density long-chain hydrocarbons [3]. Innovative System Design - The research team from Beijing University of Chemical Technology has developed a modular design integrating CO2 electro-catalytic reduction with microbial fermentation, published in Advanced Energy Materials [4][13]. - The electro-catalytic system employs tannic acid-based metal-polyphenol complex nanoparticles to synthesize a covalent organic polymer catalyst, achieving high selectivity and current density for ethanol production [7][12]. Performance Evaluation - The MPN@deCOP@Ag-Cu2O catalyst demonstrated a Faradaic efficiency (FE) for ethanol of approximately 44.5% at a current density of 400 mA cm², outperforming traditional copper catalysts [12]. - The system maintained ethanol selectivity around 25% over a prolonged operation of 5.8 hours, with a product purity of 86.6% [12][13]. Microbial Conversion - Engineered E. coli strains were developed to convert ethanol into industrially valuable products such as itaconic acid, isopropanol, and polyhydroxybutyrate (PHB) [16]. - The study achieved significant yields of 482.6 mg/L for itaconic acid, 109.3 mg/L for isopropanol, and 295.1 mg/L for PHB, demonstrating the feasibility of using CO2-derived ethanol as a sustainable carbon source [16]. Future Implications - The findings suggest that the developed electro-catalysts and reactor designs have significant potential for scaling up CO2 conversion processes, addressing key challenges in CO2 RR technology applications [13].