Enzymes have evolved to catalyse challenging chemical transformations with high efficiency and selectivity. Although a number of artificial systems have been developed to recapitulate the catalytic activity of natural enzymes, they are mostly limited to catalysing relatively simple reactions owing to their ability to mimic only the active metal centres of natural enzymes, without incorporating the proximal amino acids or cofactors. Here we report a metal–organic framework-based artificial enzyme (metal–organic–zyme, MOZ) by integrating active metal centres, proximal amino acids and other cofactors into a tunable metal–organic framework monolayer. We design two libraries of MOZs to perform photocatalytic CO2 reduction and water oxidation reactions. Through tuning the incorporated amino acids in the MOZs, we systematically optimize the activity and selectivity of these libraries. Combining these optimized MOZs into a single system realizes complete artificial photosynthesis in the reaction of (1 + n)CO2 + 2H2O → CH4 + nCO + (2 + n/2)O2.
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Data relating to the characterization data of materials, detection of products, mechanistic studies, computational studies and NMR spectra are available in the Supplementary Information. Crystallographic data for the structures reported in this article have been deposited at the Cambridge Crystallographic Data Centre, under deposition numbers CCDC 2000080 (Ur). Copies of the data can be obtained free of charge via https://www.ccdc.cam.ac.uk/structures/. Cartesian coordinates of optimized structures are available in Supplementary Data 1. All additional data are available from the authors upon reasonable request.
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We thank F. Shi for help with scanning transmission electron microscopy. This work made use of Instruments in the Electron Microscopy Core (Research Resources Center, University of Illinois at Chicago). We thank G. Zhang, X. Jiang, C. Wang and F. Shi for helpful discussions. This work was supported by the University of Chicago and National Science Foundation (CHE-2102554). W.S. acknowledges financial support from the China Scholarship Council. Single-crystal diffraction studies were performed at ChemMatCARS, APS, ANL. ChemMatCARS is principally supported by the Divisions of Chemistry (CHE) and Materials Research (DMR), National Science Foundation, under grant NSF/CHE-1346572. Use of the Advanced Photon Source, an Office of Science User Facility operated for the US Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the US DOE under contract DE-AC02-06CH11357.
The authors declare no competing interests.
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Lan, G., Fan, Y., Shi, W. et al. Biomimetic active sites on monolayered metal–organic frameworks for artificial photosynthesis. Nat Catal (2022). https://doi.org/10.1038/s41929-022-00865-5
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