Regulating the Coordination Environment of Mesopore-Confined Single Atoms from Metalloprotein-MOFs for Highly Efficient Biocatalysis

Single-atom catalysts (SACs) exhibit unparalleled atomic utilization and catalytic efficiency, yet it is challenging to modulate SACs with highly dispersed single-atoms, mesopores, and well-regulated coordination environment simultaneously and ultimately maximize their catalytic efficiency. Here, a generalized strategy to construct highly active ferric-centered SACs (Fe-SACs) is developed successfully via a biomineralization strategy that enables the homogeneous encapsulation of metalloproteins within metal-organic frameworks (MOFs) followed by pyrolysis. The results demonstrate that the constructed metalloprotein-MOF-templated Fe-SACs achieve up to 23-fold and 47-fold higher activity compared to those using metal ions as the single-atom source and those with large mesopores induced by Zn evaporation, respectively, as well as up to a 25-fold and 1900-fold higher catalytic efficiency compared to natural enzymes and natural-enzyme-immobilized MOFs. Furthermore, this strategy can be generalized to a variety of metal-containing metalloproteins and enzymes. The enhanced catalytic activity of Fe-SACs benefits from the highly dispersed atoms, mesopores, as well as the regulated coordination environment of single-atom active sites induced by metalloproteins. Furthermore, the developed Fe-SACs act as an excellent and effective therapeutic platform for suppressing tumor cell growth. This work advances the development of highly efficient SACs using metalloproteins-MOFs as a template with diverse biotechnological applications.

Automated summary

This study successfully developed a generalized strategy to construct highly active ferric-centered single-atom catalysts (Fe-SACs) and demonstrated their superior performance in catalytic reactions and suppressing tumor cell growth. The strategy can be generalized to different metalloproteins and enzymes, providing new possibilities for the development of efficient SACs.