Integrating Photocatalysis and Biosynthesis for Upgrading CO ₂ into Single-Cell Protein

Energy dilemmas and environmental degradation have emerged as interconnected challenges that command extensive global attention. Herein, we report an integrated strategy through integrating photocatalysis and biosynthesis for producing single-cell protein (SCP), utilizing carbon dioxide (CO2) as the carbon source. First, Eu-doped NiAl-layered double hydroxides (Eu-NiAl-LDHs) were rationally designed via orbital coupling engineering for photocatalytic-driven CO2 reduction, enabling the effective synthesis of syngas (CO and H2) with tunable composition. Moving downstream to the biosynthetic phase, Hydrogenophaga pseudoflava Z-1107 was strategically utilized to transform the precursor syngas into SCP, with a cell dry weight of 566 mg L–1. This work thus demonstrates a potential route toward a carbon-negative solution of upgrading CO2.