Bulk- and Surface-Engineered Carbon Nitride with Promoted Electron Transfer for NADH Regeneration and Artificial Photosynthesis

Abstract

Carbon nitride (CN), a well-known photocatalyst, has been extensively utilized in light-driven redox reactions, including NADH regeneration. However, its catalytic efficiency is hindered by rapid charge recombination due to obstructed electron transfer. Herein, we developed a highly porous CN coated with a thin layer of rhodium complex (Rh*-PCN) through a combination of bulk and surface engineering for enhanced NADH regeneration. The bulk-engineered porous network of PCN facilitates oriented electron transfer in Rh*-PCN, while the surface-engineered Rh layer minimizes the electron transfer distance between PCN and the rhodium complex. Rh*-PCN achieves an initial NADH regeneration rate of 16.80 mmol g⁻¹ h⁻¹. Moreover, Rh*-PCN suppresses enzyme deactivation by compartmentalizing the enzyme from the photogenerated holes on PCN and the rhodium complex. When integrated with glutamate dehydrogenase, the Rh*-PCN/enzyme coupled system produces L-glutamic acid.