Research ArticleMATERIALS SCIENCE

Single-atom nanozymes

See allHide authors and affiliations

Science Advances  03 May 2019:
Vol. 5, no. 5, eaav5490
DOI: 10.1126/sciadv.aav5490
  • Fig. 1 Synthetic scheme and morphology characterization of FeN5SA/CNF.

    (A) Schematic formation process of carbon nanoframe–confined atomically dispersed Fe sites with axial five-N coordination for mimicking the active center of cytocrome P450. (B and C) TEM images and (D) high-angle annular dark-field STEM (HAADF-STEM) image of FeN5 SA/CNF. (E and F) Magnified HAADF-STEM images of FeN5 SA/CNF showing the dominant metal single atom. (G) EELS mapping images of FeN5 SA/CNF of the selected region in (D). Scale bars, 1 μm and 100, 100, 5, 2, and 50 nm (B to G, respectively).

  • Fig. 2 Atomic structure characterization of FeN5SA/CNF.

    (A) XPS spectrum of N 1s. a.u., arbitrary unit. (B) Normalized XANES spectra at Fe K-edge of the Fe foil, Fe2O3, FePc, and FeN5 SA/CNF and (C) the corresponding k3-weighted Fourier-transformed spectra. (D) Fitting curves of the EXAFS of FeN5 SA/CNF in the r-space and k-space [inset of (D)].

  • Fig. 3 Oxidase-like activity of FeN5SA/CNF.

    (A) Schematic illustration of oxidase-like characteristics of FeN5 SA/CNF–catalyzed TMB oxidation. (B) Ultraviolet-visible (UV-vis) absorption spectra of FeN5 SA/CNF in O2-saturated, air-saturated, and N2-saturated sodium acetate–acetic acid buffer. (C) The durability of FeN5 SA/CNF treated with acid (alkali) for 21 hours. (D) Time-dependent absorbance changes at 652 nm, (E) histogram of V0, and (F) typical Michaelis-Menten curves in the presence of FeN5 SA/CNF (i), MnN5 SA/CNF (ii), CoN5 SA/CNF (iii), FeN4 SA/CNF (iv), NiN5 SA/CNF (v), and CuN5 SA/CNF (vi) in air-saturated sodium acetate–acetic acid buffer. The inset of (E) is an optical image of the TMB solution catalyzed by corresponding catalysts. Photo credit: Liang Huang, Changchun Institute of Applied Chemistry.

  • Fig. 4 Theoretical investigation of oxidase-like activity over FeN5SA/CNF.

    (A) Proposed reaction pathways of O2 reduction to H2O with optimized adsorption configurations on FeN5 SA/CNF. The gray, blue, purple, red, and white balls represent the C, N, Fe, O, and H atoms, respectively. (B) Free energy diagram for oxygen reduction reaction on single-atom enzyme mimics with TMB as reductant in an acidic medium.

Supplementary Materials

  • Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/5/5/eaav5490/DC1

    Fig. S1. The structures of cytocrome P450, horseradish peroxidase, and catalase and the corresponding active center.

    Fig. S2. Morphology of the Zn-MOF precursor.

    Fig. S3. Structure of the Zn-MOF precursor.

    Fig. S4. FTIR spectra of FePc, Zn-MOF, and FePc@Zn-MOF.

    Fig. S5. Morphology and structure of FeN5 SA/CNF.

    Fig. S6. Surface area and pore structure characterization.

    Fig. S7. HRTEM images of FeN5 SA/CNF.

    Fig. S8. XPS and Mössbauer spectra of FeN5 SA/CNF.

    Fig. S9. Morphology and atomic structure of FeN5 SA/CNF@800°C.

    Fig. S10. Morphology and atomic structure of FeN5 SA/CNF@1000°C.

    Fig. S11. Morphology and atomic structure of FeN4 SA/CNF.

    Fig. S12. Morphology and atomic structure of MnN5 SA/CNF.

    Fig. S13. Morphology and atomic structure of CoN5 SA/CNF.

    Fig. S14. Morphology and atomic structure of NiN5 SA/CNF.

    Fig. S15. Morphology and atomic structure of CuN5 SA/CNF.

    Fig. S16. UV-vis absorption spectra of the catalysts.

    Fig. S17. Oxidase-like activities of FeN5 SA/CNF in different conditions.

    Fig. S18. UV-vis absorption spectra of FeN5 SA/CNF.

    Fig. S19. Morphology and structure of synthesized conventional nanozymes.

    Fig. S20. UV-vis absorption spectra of TMB solutions.

    Fig. S21. Morphological changes in bacteria.

    Fig. S22. In vitro cytotoxicity experiments.

    Fig. S23. Photographs of in vivo mice wound model.

    Fig. S24. Double-reciprocal plots of activity of these catalysts.

    Fig. S25. The analysis of the intermediate state of and active center in FeN5 SA/CNF.

    Fig. S26. Theoretical investigation of oxidase-like activity.

    Table S1. Mössbauer parameters of FeN5 SA/CNF.

    Table S2. Comparison of oxidase-like activity of synthesized catalysts.

    Table S3. Comparison of the kinetic constants of the single-atom enzyme mimics.

    Table S4. The adsorption energy on the single-atom catalysts.

    Table S5. Reaction free energy of intermediate species on single-atom catalysts.

    Table S6. Comparison of the kinetic constants of FeN5 SA/CNF and nanozymes.

    References (4451)

  • Supplementary Materials

    This PDF file includes:

    • Fig. S1. The structures of cytocrome P450, horseradish peroxidase, and catalase and the corresponding active center.
    • Fig. S2. Morphology of the Zn-MOF precursor.
    • Fig. S3. Structure of the Zn-MOF precursor.
    • Fig. S4. FTIR spectra of FePc, Zn-MOF, and FePc@Zn-MOF.
    • Fig. S5. Morphology and structure of FeN5 SA/CNF.
    • Fig. S6. Surface area and pore structure characterization.
    • Fig. S7. HRTEM images of FeN5 SA/CNF.
    • Fig. S8. XPS and Mössbauer spectra of FeN5 SA/CNF.
    • Fig. S9. Morphology and atomic structure of FeN5 SA/CNF@800°C.
    • Fig. S10. Morphology and atomic structure of FeN5 SA/CNF@1000°C.
    • Fig. S11. Morphology and atomic structure of FeN4 SA/CNF.
    • Fig. S12. Morphology and atomic structure of MnN5 SA/CNF.
    • Fig. S13. Morphology and atomic structure of CoN5 SA/CNF.
    • Fig. S14. Morphology and atomic structure of NiN5 SA/CNF.
    • Fig. S15. Morphology and atomic structure of CuN5 SA/CNF.
    • Fig. S16. UV-vis absorption spectra of the catalysts.
    • Fig. S17. Oxidase-like activities of FeN5 SA/CNF in different conditions.
    • Fig. S18. UV-vis absorption spectra of FeN5 SA/CNF.
    • Fig. S19. Morphology and structure of synthesized conventional nanozymes.
    • Fig. S20. UV-vis absorption spectra of TMB solutions.
    • Fig. S21. Morphological changes in bacteria.
    • Fig. S22. In vitro cytotoxicity experiments.
    • Fig. S23. Photographs of in vivo mice wound model.
    • Fig. S24. Double-reciprocal plots of activity of these catalysts.
    • Fig. S25. The analysis of the intermediate state of and active center in FeN5 SA/CNF.
    • Fig. S26. Theoretical investigation of oxidase-like activity.
    • Table S1. Mössbauer parameters of FeN5 SA/CNF.
    • Table S2. Comparison of oxidase-like activity of synthesized catalysts.
    • Table S3. Comparison of the kinetic constants of the single-atom enzyme mimics.
    • Table S4. The adsorption energy on the single-atom catalysts.
    • Table S5. Reaction free energy of intermediate species on single-atom catalysts.
    • Table S6. Comparison of the kinetic constants of FeN5 SA/CNF and nanozymes.
    • References (4451)

    Download PDF

    Files in this Data Supplement:

Stay Connected to Science Advances

Navigate This Article