Interfacial-Engineered Fe-Aminoclay/g-C3N4 Heterojunction for Efficient NADH Regeneration and Methanol Production

The high cost of nicotinamide adenine dinucleotide (NADH) severely limits its industrial application. The present study addresses this challenge by developing a two-dimensional (2D)/2D Fe-aminoclay/g-C₃N₄ heterojunction photocatalyst (FeAC/g-C₃N₄) through an innovative nonsemiconductor cocatalyst mediation strategy. Critically, unlike conventional semiconductor cocatalysts, Fe-aminoclay (FeAC) eliminates competitive light absorption while simultaneously providing three interconnected advantages: intimate face-to-face interfacial contact enabling shortened electron transport distances that promote electron transfer and migration, embedded Fe³⁺/Fe²⁺ redox centers acting as efficient electron traps to suppress electron–hole recombination, and inherent biocompatibility enabling direct enzyme coupling. Systematic characterization demonstrates enhanced light-harvesting capability and accelerated electron-transfer efficiency in the FeAC/g-C₃N₄ heterostructure compared to those of pristine g-C₃N₄, collectively achieving an 80.79% NADH regeneration efficiency. Furthermore, practical utility is demonstrated through continuous enzymatic methanol synthesis via yeast alcohol dehydrogenase integration, maintaining a stable production over multiple cycles. These findings provide crucial design principles for developing efficient and integrated artificial photosynthetic systems for sustainable chemical synthesis.