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

Abstract

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.