Assembly of COFs layer and electron mediator on silica for visible light driven photocatalytic NADH regeneration

Photocatalytic regeneration of the high-cost co-factor NADH is a promising method to couple photo-enzyme catalysis, however, the usage of homogeneous electron mediator ([Cp*Rh(bpy)H2O]2+) which deactivates enzymes deteriorates the whole process efficiency. Herein, we report the immobilization of electron mediator ([Cp*Rh(bpy)H2O]2+) on covalent organic frameworks (COFs) by the sequential assembly method. The resultant bi-functional photocatalyst with controlled cascade electron transfer afforded NADH production rate of 9.8 mmol·gCOF−1·h−1, much higher than previously reported ones with integrated electron mediator. The photo-enzyme coupling system with the photocatalyst and alcohol dehydrogenase could continuously produce butanol for at least 180 min under visible light irradiation, implying the potential application of bi-functional photocatalyst in artificial photosynthesis.