Daeeun Choi, Seonhye Park, Jinwoo Lee
Efficient and durable catalysts are essential for enhancing the rate of CO 2 hydration in aqueous capture systems and addressing the environmental challenges posed by rising atmospheric CO 2 levels. Traditional capture methods that rely on strongly alkaline solvents face substantial drawbacks, including high regeneration energy costs and safety concerns owing to harmful byproducts. Carbonic anhydrase (CA), a zinc-containing metalloenzyme, catalyzes CO 2 hydration at near-diffusion-limited rates but rapidly degrades in real-world environments. Although various CA-mimetic catalysts have been investigated, they frequently exhibit poor durability and structural stability. In this study, we introduce ZnNC900, a robust Zn single-atom nanozyme derived from a zeolitic imidazolate framework (ZIF-8) through controlled carbonization. ZnNC900 exhibited remarkable catalytic activity for the p -nitrophenyl acetate esterase reaction, which was attributed to its CA-resembling single-atomic Zn sites. Furthermore, surface functionalization with amine-terminalized polyethylene glycol improves the colloidal stability and catalytic performance of ZnNC900 by enhancing its hydrophilicity and CO 2 affinity. These enhancements highlight the potential of ZnNC900 as a durable and efficient catalyst for aqueous CO 2 capture.