Platinum-based heterogeneous catalysts are critical to many important commercial chemical processes, but their efficiency is extremely low on a per metal atom basis, because only the surface active-site atoms are used. Catalysts with single-atom dispersions are thus highly desirable to maximize atom efficiency, but making them is challenging. Here we report the synthesis of a single-atom catalyst that consists of only isolated single Pt atoms anchored to the surfaces of iron oxide nanocrystallites. This single-atom catalyst has extremely high atom efficiency and shows excellent stability and high activity for both CO oxidation and preferential oxidation of CO in H2. Density functional theory calculations show that the high catalytic activity correlates with the partially vacant 5d orbitals of the positively charged, high-valent Pt atoms, which help to reduce both the CO adsorption energy and the activation barriers for CO oxidation.
Subscribe to Journal
Get full journal access for 1 year
only $13.33 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Haruta, M. Size- and support-dependency in the catalysis of gold. Catal. Today 36, 153–166 (1997).
Chen, M. & Goodman, D. W. The structure of catalytically active gold on titania. Science 306, 252–255 (2004).
Herzing, A. A., Kiely, C. J., Carley, A. F., Landon, P. & Hutchings, G. J. Identification of active gold nanoclusters on iron oxide supports for CO oxidation. Science 321, 1331–1335 (2008).
Turner, M. et al. Selective oxidation with dioxygen by gold nanoparticle catalysts derived from 55-atom clusters. Nature 454, 981–983 (2008).
Vajda, S. et al. Subnanometre platinum clusters as highly active and selective catalysts for the oxidative dehydrogenation of propane. Nature Mater. 8, 213–216 (2009).
Judai, K., Abbet, S., Worz, A. S., Heiz, U. & Henry, C. R. Low-temperature cluster catalysis. J. Am. Chem. Soc. 126, 2732–2737 (2004).
Lei, Y. et al. Increased silver activity for direct propylene epoxidation via subnanometer size effects. Science 328, 224–228 (2010).
Remediakis, I. N., Lopez, N. & Nørskov, J. K. CO oxidation on rutile-supported Au nanoparticles. Angew. Chem. Int. Ed. 44, 1824–1826 (2005).
Uzun, A., Ortalan, V., Browning, N. D. & Gates, B. C. A site-isolated mononuclear iridium complex catalyst supported on MgO: characterization by spectroscopy and aberration-corrected scanning transmission electron microscopy. J. Catal. 269, 318–328 (2010).
Uzun, A., Ortalan, V., Hao, Y., Browning, N. D. & Gates, B. C. Nanoclusters of gold on a high-area support: almost uniform nanoclusters imaged by scanning transmission electron microscopy. ACS Nano 3, 3691–3695 (2009).
Kaden, W. E., Wu, T., Kunkel, W. A. & Anderson, S. L. Electronic structure controls reactivity of size-selected Pd clusters adsorbed on TiO2 surfaces. Science 326, 826–829 (2009).
Böhme, D. K. & Schwarz, H. Gas-phase catalysis by atomic and cluster metal ions: the ultimate single-site catalysts. Angew. Chem. Int. Ed. 44, 2336–2354 (2005).
Lee, S. S., Fan, C. Y., Wu, T. P. & Anderson, S. L. CO oxidation on Aun/TiO2 catalysts produced by size-selected cluster deposition. J. Am. Chem. Soc. 126, 5682–5683 (2004).
Yoon, B. et al. Charging effects on bonding and catalyzed oxidation of CO on Au8 clusters on MgO. Science 307, 403–407 (2005).
Matthey, D. et al. Enhanced bonding of gold nanoparticles on oxidized TiO2(110). Science 315, 1692–1696 (2007).
Kwak, J. H. et al. Coordinatively unsaturated Al3+ centers as binding sites for active catalyst phases of platinum on γ-Al2O3 . Science 325, 1670–1673 (2009).
Qiao, B. & Deng, Y. Highly effective ferric hydroxide supported gold catalyst for selective oxidation of CO in the presence of H2 . Chem. Commun. 2192–2193 (2003).
Qiao, B., Liu, L., Zhang, J. & Deng, Y. Preparation of highly effective ferric hydroxide supported noble metal catalysts for CO oxidations: from gold to palladium. J. Catal. 261, 241–244 (2009).
Nellist, P. D. & Pennycook, S. J. Direct imaging of the atomic configuration of ultradispersed catalysts. Science 274, 413–415 (1996).
Pennycook, S. J. Z-contrast stem for materials science. Ultramicroscopy 30, 58–69 (1989).
Wang, S. et al. Dopants adsorbed as single atoms prevent degradation of catalysts. Nature Mater. 3, 143–146 (2004).
Nellist, P. D. et al. Direct sub-angstrom imaging of a crystal lattice. Science 305, 1741–1741 (2004).
Sohlberg, K., Rashkeev, S., Borisevich, A. Y., Pennycook, S. J. & Pantelides, S. T. Origin of anomalous Pt–Pt distances in the Pt/alumina catalytic system. ChemPhysChem 5, 1893–1897 (2004).
Pennycook, S. J. et al. Aberration-corrected scanning transmission electron microscopy: from atomic imaging and analysis to solving energy problems. Phil. Trans. R. Soc. A 367, 3709–3733 (2009).
Ortalan, V., Uzun, A., Gates, B. C. & Browning, N. D. Direct imaging of single metal atoms and clusters in the pores of dealuminated HY zeolite. Nature Nanotech. 5, 506–510 (2010).
Li, Z. Y. et al. Three-dimensional atomic-scale structure of size-selected gold nanoclusters. Nature 451, 46–48 (2008).
Allard, L. F. et al. Evolution of gold structure during thermal treatment of Au/FeOx catalysts revealed by aberration-corrected electron microscopy. J. Electron Microsc. (Tokyo) 58, 199–212 (2009).
Chang, J-R., Koningsberger, D. C. & Gates, B. C. Structurally simple supported platinum clusters prepared from [Pt15(CO)30]2− on magnesium oxide. J. Am. Chem. Soc. 114, 6460–6466 (1992).
Xiao, L. & Wang, L. Structures of platinum clusters: planar or spherical? J. Phys. Chem. A 108, 8605–8614 (2004).
Yoshida, H. et al. XANES study of the support effect on the state of platinum catalysts. J. Synchrotron Radiat. 6, 471–473 (1999).
Pozdnyakova, O. et al. Preferential CO oxidation in hydrogen (PROX) on ceria-supported catalysts, part I: oxidation state and surface species on Pt/CeO2 under reaction conditions. J. Catal. 237, 1–16 (2006).
Greenler, R. G. et al. Stepped single-crystal surfaces as models for small catalyst particles. Surf. Sci. 152–153, 338–345 (1985).
Brandt, R. K., Hughes, M. R., Bourget, L. P., Truszkowska, K. & Greenler, R. G. The interpretation of CO adsorbed on Pt/SiO2 of two different particle-size distributions. Surf. Sci. 286, 15–25 (1993).
Kappers, M. & Maas, J. Correlation between CO frequency and Pt coordination number. A DRIFT study on supported Pt catalysts. Catal. Lett. 10, 365–373 (1991).
Hadjiivanov, K. I. & Vayssilov, G. N. Characterization of oxide surfaces and zeolites by carbon monoxide as an IR probe molecule. Adv. Catal. 47, 307–511 (2002).
Bazin, P., Saur, O., Lavalley, J. C., Daturi, M. & Blanchard, G. FT-IR study of CO adsorption on Pt/CeO2: characterisation and structural rearrangement of small Pt particles. Phys. Chem. Chem. Phys. 7, 187–194 (2005).
Gruene, P., Fielicke, A., Meijer, G. & Rayner, D. M. The adsorption of CO on group 10 (Ni, Pd, Pt) transition-metal clusters. Phys. Chem. Chem. Phys. 10, 6144–6149 (2008).
Xie, X., Li, Y., Liu, Z-Q., Haruta, M. & Shen, W. Low-temperature oxidation of CO catalysed by Co3O4 nanorods. Nature 458, 746–749 (2009).
Fu, Q. et al. Interface-confined ferrous centers for catalytic oxidation. Science 328, 1141–1144 (2010).
Haruta, M., Yamada, N., Kobayashi, T. & Iijima, S. Gold catalysts prepared by coprecipitation for low-temperature oxidation of hydrogen and of carbon monoxide. J. Catal. 115, 301–309 (1989).
Haruta, M. Catalysis of gold nanoparticles deposited on metal oxides. CATTECH 6, 102–115 (2002).
Huang, Y. Q., Wang, A. Q., Wang, X. D. & Zhang, T. Preferential oxidation of CO under excess H2 conditions over iridium catalysts. Int. J. Hydrogen Energy 32, 3880–3886 (2007).
Wang, X. G. et al. The hematite (α-Fe2O3) (0001) surface: evidence for domains of distinct chemistry. Phys. Rev. Lett. 81, 1038–1041 (1998).
Yamamoto, S. et al. Water adsorption on α-Fe2O3 (0001) at near ambient conditions. J. Phys. Chem. C 114, 2256–2266 (2010).
Jin, J. J., Ma, X. Y., Kim, C. Y., Ellis, D. E. & Bedzyk, M. J. Adsorption of V on a hematite (0001) surface and its oxidation: submonolayer coverage. Surf. Sci. 601, 3082–3098 (2007).
Lübbe, M. & Moritz, W. A LEED analysis of the clean surfaces of α-Fe2O3 (0001) and α-Cr2O3 (0001) bulk single crystals. J. Phys.: Condens. Matter 21, 134010 (2009).
Wasserman, E., Rustad, J. R., Felmy, A. R., Hay, B. P. & Halley, J. W. Ewald methods for polarizable surfaces with application to hydroxylation and hydrogen bonding on the (012) and (001) surfaces of α-Fe2O3 . Surf. Sci. 385, 217–239 (1997).
Thevuthasan, S. et al. Surface structure of MBE-grown α-Fe2O3(0001) by intermediate-energy X-ray photoelectron diffraction. Surf. Sci. 425, 276–286 (1999).
Alavi, A., Hu, P., Deutsch, T., Silvestrelli, P. L. & Hutter, J. CO oxidation on Pt(111): an ab initio density functional theory study. Phys. Rev. Lett. 80, 3650–3653 (1998).
Fu, Q., Saltsburg, H. & Flytzani-Stephanopoulos, M. Active nonmetallic Au and Pt species on ceria-based water–gas shift catalysts. Science 301, 935–938 (2003).
We thank Y. Huang, S. Zhang, T. Hu, J. Zhang, Y. Xie and L. Zheng for their help in the EXAFS measurements and data analysis, and L. Li for infrared measurements and discussion. We also acknowledge E. Okunishi for assistance on operating the JEM ARM-200F TEM/STEM. Particularly, we thank Jeffrey T. Miller for his suggestions and comments on EXAFS analysis during the manuscript revision process. Financial support for this research work from the National Science Foundation of China (20325620, 20773124) and the Ministry of Science and Technology of China (NKBRSF 2007CB815200, 2011CB932400) is also acknowledged. Part of the electron microscopy work was conducted at the Oak Ridge National Laboratory's High Temperature Materials Laboratory, sponsored by the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Program. The calculations were performed at the Shanghai Supercomputing Center and the Computer Network Information Center, Chinese Academy of Sciences.
The authors declare no competing financial interests.
About this article
Cite this article
Qiao, B., Wang, A., Yang, X. et al. Single-atom catalysis of CO oxidation using Pt1/FeOx. Nature Chem 3, 634–641 (2011). https://doi.org/10.1038/nchem.1095
Progress in Materials Science (2021)
Identifying the Zn–Co binary as a robust bifunctional electrocatalyst in oxygen reduction and evolution reactions via shifting the apexes of the volcano plot
Journal of Energy Chemistry (2021)
Orbital symmetry matching: Achieving superior nitrogen reduction reaction over single-atom catalysts anchored on Mxene substrates
Chinese Journal of Catalysis (2021)
Journal of Energy Chemistry (2021)
Theoretical screening of the transition metal heteronuclear dimer anchored graphdiyne for electrocatalytic nitrogen reduction
Journal of Energy Chemistry (2021)