Visible Light‐Driven CO ₂ ‐to‐Methanol Conversion Using Chlorophyll‐Integrated Enzyme‐Alginate Biohybrids

Abstract The rapid pace of industrialization and urbanization, while central to economic growth, has led to a significant increase in atmospheric carbon dioxide (CO 2 ), contributing to global climate change. Mitigating CO 2 emissions through efficient and sustainable technologies is imperative. In this study, we report a novel and eco‐friendly approach for photocatalytic CO 2 reduction to methanol using an enzyme‐coupled alginate bead system integrated with a visible‐light‐active chlorophyll‐based photosensitizer. The biohybrid system demonstrated enhanced CO 2 conversion efficiency under visible light conditions. Using free‐form dehydrogenases, a methanol yield of 2.6 ± 0.17 g/L was achieved. Upon immobilization of the enzymes within the alginate matrix and chlorophyll, the yield increased to 5.2 ± 0.27 g/L, associated with the creation of a favorable microenvironment characterized by high hydrophilicity, optimal mechanical properties, efficient substrate diffusion, and confinement effects. This work highlsights the potential of photosynthetic biohybrid systems as a sustainable platform for CO 2 valorization and green fuel production.