Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

General synthesis of single-atom catalysts with high metal loading using graphene quantum dots

Nature Chemistry volume 13, pages 887–894 (2021)Cite this article

Subjects

Abstract

Transition-metal single-atom catalysts present extraordinary activity per metal atomic site, but suffer from low metal-atom densities (typically less than 5 wt% or 1 at.%), which limits their overall catalytic performance. Here we report a general method for the synthesis of single-atom catalysts with high transition-metal-atom loadings of up to 40 wt% or 3.8 at.%, representing several-fold improvements compared to benchmarks in the literature. Graphene quantum dots, later interweaved into a carbon matrix, were used as a support, providing numerous anchoring sites and thus facilitating the generation of high densities of transition-metal atoms with sufficient spacing between the metal atoms to avoid aggregation. A significant increase in activity in electrochemical CO2 reduction (used as a representative reaction) was demonstrated on a Ni single-atom catalyst with increased Ni loading.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it

$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Schematic illustration of the synthesis process of single-atom catalysts using different strategies.
Fig. 2: Synthesis and characterization of atomically dispersed iridium catalyst with iridium content of approximately 41 wt% and 3.84 at.%.
Fig. 3: Characterization of atomically dispersed iridium catalyst with iridium content of ~41 wt%.
Fig. 4: Generality of the GQD-assisted strategy for synthesizing atomically dispersed TM catalysts with high metal content.

Data availability

The authors declare that all of the data supporting the findings of this study are available within the paper and the Supplementary Information, and also from the corresponding authors upon reasonable request. Source data are provided with this paper.

References

  1. Qiao, B. et al. Single-atom catalysis of CO oxidation using Pt1/FeOx. Nat. Chem. 3, 634–641 (2011).

    Article  CAS  PubMed  Google Scholar 

  2. Sun, X. et al. Facile synthesis of precious-metal single-site catalysts using organic solvents. Nat. Chem. 12, 560–567 (2020).

    Article  CAS  PubMed  Google Scholar 

  3. Zhang, L., Ren, Y., Liu, W., Wang, A. & Zhang, T. Single-atom catalyst: a rising star for green synthesis of fine chemicals. Natl Sci. Rev. 5, 653–672 (2018).

    Article  CAS  Google Scholar 

  4. Ji, S. et al. Chemical synthesis of single atomic site catalysts. Chem. Rev. 120, 11900–11955 (2020).

    Article  CAS  PubMed  Google Scholar 

  5. Chen, Y. et al. Single-atom catalysts: synthetic strategies and electrochemical applications. Joule 2, 1242–1264 (2018).

    Article  CAS  Google Scholar 

  6. Liu, P. et al. Photochemical route for synthesizing atomically dispersed palladium catalysts. Science 352, 797–800 (2016).

    Article  CAS  PubMed  Google Scholar 

  7. Lu, Y. et al. Identification of the active complex for CO oxidation over single-atom Ir-on-MgAl2O4 catalysts. Nat. Catal. 2, 149–156 (2019).

    Article  CAS  Google Scholar 

  8. Jones, J. et al. Thermally stable single-atom platinum-on-ceria catalysts via atom trapping. Science 353, 150–154 (2016).

    Article  CAS  PubMed  Google Scholar 

  9. Back, S., Lim, J., Kim, N.-Y., Kim, Y.-H. & Jung, Y. Single-atom catalysts for CO2 electroreduction with significant activity and selectivity improvements. Chem. Sci. 8, 1090–1096 (2017).

    Article  CAS  PubMed  Google Scholar 

  10. Darby, M. T., Stamatakis, M., Michaelides, A. & Sykes, E. C. H. Lonely atoms with special gifts: breaking linear scaling relationships in heterogeneous catalysis with single-atom alloys. J. Phys. Chem. Lett. 9, 5636–5646 (2018).

    Article  CAS  PubMed  Google Scholar 

  11. Gani, T. Z. & Kulik, H. J. Understanding and breaking scaling relations in single-site catalysis: methane to methanol conversion by FeIV═O. ACS Catal. 8, 975–986 (2018).

    Article  CAS  Google Scholar 

  12. Gu, J., Hsu, C.-S., Bai, L., Chen, H. M. & Hu, X. Atomically dispersed Fe3+ sites catalyze efficient CO2 electroreduction to CO. Science 364, 1091–1094 (2019).

    Article  CAS  PubMed  Google Scholar 

  13. Xiong, Y. et al. Single-atom Rh/N-doped carbon electrocatalyst for formic acid oxidation. Nat. Nanotechnol. 15, 390–397 (2020).

    Article  CAS  PubMed  Google Scholar 

  14. Zheng, T. et al. Large-scale and highly selective CO2 electrocatalytic reduction on nickel single-atom catalyst. Joule 3, 265–278 (2019).

    Article  CAS  Google Scholar 

  15. Malta, G. et al. Identification of single-site gold catalysis in acetylene hydrochlorination. Science 355, 1399–1403 (2017).

    Article  CAS  PubMed  Google Scholar 

  16. Wu, J., Xiong, L., Zhao, B., Liu, M. & Huang, L. Densely populated single atom catalysts. Small Methods 4, 1900540 (2019).

    Article  CAS  Google Scholar 

  17. Wang, L. et al. A sulfur-tethering synthesis strategy toward high-loading atomically dispersed noble metal catalysts. Sci. Adv. 5, eaax6322 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Gawande, M. B., Fornasiero, P. & Zbořil, R. Carbon-based single-atom catalysts for advanced applications. ACS Catal. 10, 2231–2259 (2020).

    Article  CAS  Google Scholar 

  19. Bakandritsos, A. et al. Mixed-valence single-atom catalyst derived from functionalized graphene. Adv. Mater. 31, 1900323 (2019).

    Article  CAS  Google Scholar 

  20. Zhang, Z. et al. Electrochemical deposition as a universal route for fabricating single-atom catalysts. Nat. Commun. 11, 1215 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. He, X. et al. A versatile route to fabricate single atom catalysts with high chemoselectivity and regioselectivity in hydrogenation. Nat. Commun. 10, 3663 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  22. Zhao, L. et al. Cascade anchoring strategy for general mass production of high-loading single-atomic metal-nitrogen catalysts. Nat. Commun. 10, 1278 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  23. Fei, H. et al. General synthesis and definitive structural identification of MN4C4 single-atom catalysts with tunable electrocatalytic activities. Nat. Catal. 1, 63–72 (2018).

    Article  CAS  Google Scholar 

  24. Qu, Y. et al. Ambient synthesis of single-atom catalysts from bulk metal via trapping of atoms by surface dangling bonds. Adv. Mater. 31, 1904496 (2019).

    Article  CAS  Google Scholar 

  25. Liu, K. et al. Strong metal-support interaction promoted scalable production of thermally stable single-atom catalysts. Nat. Commun. 11, 1263 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Zhu, Y. et al. A cocoon silk chemistry strategy to ultrathin N-doped carbon nanosheet with metal single-site catalysts. Nat. Commun. 9, 3861 (2018).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  27. Jiang, K. et al. Highly selective oxygen reduction to hydrogen peroxide on transition metal single atom coordination. Nat. Commun. 10, 3997 (2019).

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  28. Du, Z. et al. Cobalt in nitrogen-doped graphene as single-atom catalyst for high-sulfur content lithium–sulfur batteries. J. Am. Chem. Soc. 141, 3977–3985 (2019).

    Article  CAS  PubMed  Google Scholar 

  29. Deng, D. et al. A single iron site confined in a graphene matrix for the catalytic oxidation of benzene at room temperature. Sci. Adv. 1, e1500462 (2015).

    Article  PubMed  PubMed Central  Google Scholar 

  30. Jung, E. et al. Atomic-level tuning of Co–N–C catalyst for high-performance electrochemical H2O2 production. Nat. Mater. 19, 436–442 (2020).

    Article  CAS  PubMed  Google Scholar 

  31. Liu, W. et al. Single-atom dispersed Co–N–C catalyst: structure identification and performance for hydrogenative coupling of nitroarenes. Chem. Sci. 7, 5758–5764 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Wang, J. et al. Amino-functionalized Fe3O4@SiO2 core-shell magnetic nanomaterial as a novel adsorbent for aqueous heavy metals removal. J. Colloid Interface Sci. 349, 293–299 (2010).

    Article  CAS  PubMed  Google Scholar 

  33. Chen, G. et al. Assembling carbon quantum dots to a layered carbon for high-density supercapacitor electrodes. Sci. Rep. 6, 19028 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Wang, L. et al. Gram-scale synthesis of single-crystalline graphene quantum dots with superior optical properties. Nat. Commun. 5, 5357 (2014).

    Article  CAS  PubMed  Google Scholar 

  35. Kumar, G. S. et al. Amino-functionalized graphene quantum dots: origin of tunable heterogeneous photoluminescence. Nanoscale 6, 3384–3391 (2014).

    Article  PubMed  CAS  Google Scholar 

  36. Allahbakhsh, A. & Bahramian, A. R. Self-assembly of graphene quantum dots into hydrogels and cryogels: dynamic light scattering, UV–Vis spectroscopy and structural investigations. J. Mol. Liq. 265, 172–180 (2018).

    Article  CAS  Google Scholar 

  37. Gelfond, N. et al. An XPS study of the composition of iridium films obtained by MO CVD. Surf. Sci. 275, 323–331 (1992).

    Article  CAS  Google Scholar 

  38. Wang, G. et al. Selective growth of IrO2 nanorods using metalorganic chemical vapor deposition. J. Mater. Chem. 16, 780–786 (2006).

    Article  CAS  Google Scholar 

  39. Xiao, M. et al. A single-atom iridium heterogeneous catalyst in oxygen reduction reaction. Angew. Chem. Int. Ed. 131, 9742–9747 (2019).

    Article  Google Scholar 

  40. Hall, S. C., Subramanian, V., Teeter, G. & Rambabu, B. Influence of metal–support interaction in Pt/C on CO and methanol oxidation reactions. Solid State Ion. 175, 809–813 (2004).

    Article  CAS  Google Scholar 

  41. Yang, H. B. et al. Atomically dispersed Ni(i) as the active site for electrochemical CO2 reduction. Nat. Energy 3, 140–147 (2018).

    Article  CAS  Google Scholar 

  42. Jiang, K. et al. Transition-metal single atoms in a graphene shell as active centers for highly efficient artificial photosynthesis. Chem 3, 950–960 (2017).

    Article  CAS  Google Scholar 

  43. Koshy, D. et al. Understanding the origin of highly selective CO2 electroreduction to CO on Ni,N-doped carbon catalysts. Angew. Chem. Int. Ed. 59, 4043–4050 (2020).

    Article  CAS  Google Scholar 

  44. Zhang, G. et al. A general route via formamide condensation to prepare atomically dispersed metal–nitrogen–carbon electrocatalysts for energy technologies. Energy Environ. Sci. 12, 1317–1325 (2019).

    Article  CAS  Google Scholar 

  45. Liu, W. et al. A durable nickel single-atom catalyst for hydrogenation reactions and cellulose valorization under harsh conditions. Angew. Chem. Int. Ed. 130, 7189–7193 (2018).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by Rice University and the Welch Foundation Research Grant C-2051-20200401. H.W. is a CIFAR Azrieli Global Scholar in the Bio-inspired Solar Energy Program. C.X. acknowledges support from a J. Evans Attwell-Welch Postdoctoral Fellowship. C.X. acknowledges the University of Electronic Science and Technology of China for startup funding (A1098531023601264). This work was performed in part at the Shared Equipment Authority at Rice University. H.N.A. acknowledges support from King Abdullah University of Science and Technology. XAS and PDF measurements were conducted at the Canadian Light Source, which is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), National Research Council Canada (NRC) and University of Saskatchewan. Electron microscopy was conducted at the Center for Nanophase Materials Sciences, which is a U.S. Department of Energy Office of Science User Facility.

Author information

Authors and Affiliations

  1. Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, USA

    Chuan Xia, Yunrui Qiu, Yang Xia, Peng Zhu, Xiao Zhang, Zhenyu Wu, Jung Yoon (Timothy) Kim & Haotian Wang

  2. Smalley-Curl Institute, Rice University, Houston, TX, USA

    Chuan Xia

  3. School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu, P. R. China

    Chuan Xia

  4. Canadian Light Source, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

    Graham King, Mohsen Shakouri, Emilio Heredia & Yongfeng Hu

  5. Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA

    David A. Cullen

  6. Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia

    Dongxing Zheng, Peng Li & Husam N. Alshareef

  7. Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, P. R. China

    Peixin Cui

  8. Department of Materials Science and Nano-Engineering, Rice University, Houston, TX, USA

    Haotian Wang

  9. Department of Chemistry, Rice University, Houston, TX, USA

    Haotian Wang

  10. Azrieli Global Scholar, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada

    Haotian Wang

Authors
  1. Chuan Xia
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yunrui Qiu
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Yang Xia
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Peng Zhu
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Graham King
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Xiao Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Zhenyu Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Jung Yoon (Timothy) Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. David A. Cullen
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Dongxing Zheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Peng Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. Mohsen Shakouri
    View author publications

    You can also search for this author in PubMed Google Scholar

  13. Emilio Heredia
    View author publications

    You can also search for this author in PubMed Google Scholar

  14. Peixin Cui
    View author publications

    You can also search for this author in PubMed Google Scholar

  15. Husam N. Alshareef
    View author publications

    You can also search for this author in PubMed Google Scholar

  16. Yongfeng Hu
    View author publications

    You can also search for this author in PubMed Google Scholar

  17. Haotian Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

The project was conceptualized by C.X. and H.W. and supervised by H.W. and Y.H. Catalysts were synthesized by C.X. with the help of Y.Q.; C.X., Y.Q. and P.Z. conducted the catalytic tests and the related data processing. Materials characterization and analysis were performed by C.X. with the help of P.Z., Y.X., X.Z., Z.W., D.Z., P.L., D.A.C. and J.Y.K. The XAS test and analysis was performed by M.S., E.H., P.C. and Y.H. PDF was performed by G.K.; H.N.A provided suggestions for this study. C.X. and H.W. wrote the manuscript with input from all the authors.

Corresponding authors

Correspondence to Chuan Xia, Yongfeng Hu or Haotian Wang.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Chemistry thanks Aiqin Wang, Yuen Wu and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–27, Table 1 and references.

Source data

Source Data Fig. 2

Statistical source data.

Source Data Fig. 4

Statistical source data.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Xia, C., Qiu, Y., Xia, Y. et al. General synthesis of single-atom catalysts with high metal loading using graphene quantum dots. Nat. Chem. 13, 887–894 (2021). https://doi.org/10.1038/s41557-021-00734-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41557-021-00734-x

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing