The reversible and cooperative activation process, which includes electron transfer from surrounding redox mediators, the reversible valence change of cofactors and macroscopic functional/structural change, is one of the most important characteristics of biological enzymes, and has frequently been used in the design of homogeneous catalysts. However, there are virtually no reports on industrially important heterogeneous catalysts with these enzyme-like characteristics. Here, we report on the design and synthesis of highly active TiO2 photocatalysts incorporating site-specific single copper atoms (Cu/TiO2) that exhibit a reversible and cooperative photoactivation process. Our atomic-level design and synthetic strategy provide a platform that facilitates valence control of co-catalyst copper atoms, reversible modulation of the macroscopic optoelectronic properties of TiO2 and enhancement of photocatalytic hydrogen generation activity, extending the boundaries of conventional heterogeneous catalysts.
Subscribe to Journal
Get full journal access for 1 year
only $17.42 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.
All data are available in the main text or in the Supplementary Information.
Hisatomi, T., Kubota, J. & Domen, K. Recent advances in semiconductors for photocatalytic and photoelectrochemical water splitting. Chem. Soc. Rev. 43, 7520–7535 (2014).
Hoffmann, M. R., Martin, S. T., Choi, W. & Bahnemann, D. W. Environmental applications of semiconductor photocatalysis. Chem. Rev. 95, 69–96 (1995).
Kudo, A. & Miseki, Y. Heterogeneous photocatalyst materials for water splitting. Chem. Soc. Rev. 38, 253–278 (2009).
Montoya, J. H. et al. Materials for solar fuels and chemicals. Nat. Mater. 16, 70–81 (2017).
Cargnello, M. et al. Engineering titania nanostructure to tune and improve its photocatalytic activity. Proc. Natl Acad. Sci. USA 113, 3966–3971 (2016).
Gordon, T. R. et al. Nonaqueous synthesis of TiO2 nanocrystals using TiF4 to engineer mophology, oxygen vacancy concentration and photocatalytic activity. J. Am. Chem. Soc. 134, 6751–6761 (2012).
Choi, W., Termin, A. & Hoffmann, M. R. The role of metal ion dopants in quantum-sized TiO2: correlation between photoreactivity and charge carrier recombination dynamics. J. Phys. Chem. 98, 13669–13679 (1994).
Ran, J., Zhang, J., Yu, J., Jaroniec, M. & Qiao, S. Z. Earth-abundant cocatalysts for semiconductor-based photocatalytic water splitting. Chem. Soc. Rev. 43, 7787–7812 (2014).
Yang, H. G. et al. Anatase TiO2 single crystals with a large percentage of reactive facets. Nature 453, 638–641 (2008).
Park, S. et al. Photocatalytic hydrogen generation from hydriodic acid using methylammonium lead iodide in dynamic equilibrium with aqueous solution. Nat. Energy 2, 16185 (2016).
Guo, Q. et al. Elementary photocatalytic chemistry on TiO2 surfaces. Chem. Soc. Rev. 45, 3701–3730 (2016).
Hussain, H. et al. Structure of a model TiO2 photocatalytic interface. Nat. Mater. 16, 461–466 (2017).
Wang, A., Li, J. & Zhang, T. Heterogeneous single-atom catalysis. Nat. Rev. Chem. 2, 65–81 (2018).
Qiao, B. et al. Single-atom catalysis of CO oxidation using Pt1/FeOx. Nat. Chem. 3, 634–641 (2011).
Liu, P. et al. Photochemical route for synthesizing atomically dispersed palladium catalysts. Science 352, 797–800 (2016).
Lin, L. et al. Low-temperature hydrogen production from water and methanol using Pt/α-MoC catalysts. Nature 544, 80–83 (2017).
Choi, C. H. et al. Tuning selectivity of electrochemical reactions by atomically dispersed platinum catalyst. Nat. Commun. 7, 10922 (2016).
Shan, J., Li, M., Allard, L. F., Lee, S. & Flytzani-Stephanopoulos, M. Mild oxidation of methane to methanol or acetic acid on supported isolated rhodium catalysts. Nature 551, 605–608 (2017).
Nie, L. et al. Activation of surface lattice oxygen in single-atom Pt/CeO2 for low-temperature CO oxidation. Science 358, 1419–1423 (2017).
DeRita, L. et al. Catalyst architecture for stable single atom dispersion enables site-specific spectroscopic and reactivity measurements of CO adsorbed to Pt atoms, oxidized Pt clusters, and metallic Pt clusters on TiO2. J. Am. Chem. Soc. 139, 14150–14165 (2017).
Benkovic, S. J. & Hammes-Schiffer, S. A perspective on enzyme catalysis. Science 301, 1196–1202 (2003).
Liu, J. et al. Metalloproteins containing cytochrome, iron–sulfur, or copper redox centers. Chem. Rev. 114, 4366–4469 (2014).
Que, L. Jr & Tolman, W. B. Biologically inspired oxidation catalysis. Nature 455, 333–340 (2008).
Wodrich, M. D. & Hu, X. Natural inspirations for metal–ligand cooperative catalysis. Nat. Rev. Chem. 2, 0099 (2017).
Piao, Y. et al. Wrap–bake–peel process for nanostructural transformation from β-FeOOH nanorods to biocompatible iron oxide nanocapsules. Nat. Mater. 7, 242 (2008).
Chen, X., Liu, L., Peter, Y. Y. & Mao, S. S. Increasing solar absorption for photocatalysis with black hydrogenated titanium dioxide nanocrystals. Science 331, 746–750 (2011).
Chen, X., Liu, L. & Huang, F. Black titanium dioxide (TiO2) nanomaterials. Chem. Soc. Rev. 44, 1861–1885 (2015).
Jung, D. et al. A molecular cross-linking approach for hybrid metal oxides. Nat. Mater. 17, 341–348 (2018).
Selcuk, S., Zhao, X. & Selloni, A. Structural evolution of titanium dioxide during reduction in high-pressure hydrogen. Nat. Mater. 17, 923–928 (2018).
Zhou, W. et al. Ordered mesoporous black TiO2 as highly efficient hydrogen evolution photocatalyst. J. Am. Chem. Soc. 136, 9280–9283 (2014).
Neubert, S. et al. Highly efficient rutile TiO2 photocatalysts with single Cu(ii) and Fe(iii) surface catalytic sites. J. Mater. Chem. A 4, 3127–3138 (2016).
Siemer, N. et al. Atomic scale explanation of O2 activation at the Au–TiO2 interface. J. Am. Chem. Soc. 140, 18082–18092 (2018).
Hayyan, M., Hashim, M. A. & AlNashef, I. M. Superoxide ion: generation and chemical implications. Chem. Rev. 116, 3029–3085 (2016).
Kim, J. et al. Continuous O2-evolving MnFe2O4 nanoparticle-anchored mesoporous silica nanoparticles for efficient photodynamic therapy in hypoxic cancer. J. Am. Chem. Soc. 139, 10992–10995 (2017).
Krukau, A. V., Vydrov, O. A., Izmaylov, A. F. & Scuseria, G. E. Influence of the exchange screening parameter on the performance of screened hybrid functionals. J. Chem. Phys. 125, 224106 (2006).
Finazzi, E., Valentin, C. D., Pacchioni, G. & Selloni, A. Excess electron states in reduced bulk anatase TiO2: comparison of standard GGA, GGA + U and hybrid DFT calculations. J. Chem. Phys. 129, 154113 (2008).
Setvín, M. et al. Reaction of O2 with subsurface oxygen vacancies on TiO2 anatase (101). Science 341, 988–991 (2013).
Liu, H. et al. Crystallinity control of TiO2 hollow shells through resin-protected calcination for enhanced photocatalytic activity. Energy Environ. Sci. 8, 286–296 (2015).
Pennycook, S. J. & Jesson, D. E. High-resolution incoherent imaging of crystals. Phys. Rev. Lett. 64, 938–941 (1990).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Kresse, G. & Hafner, J. Ab initio molecular dynamics for open-shell transition metals. Phys. Rev. B 48, 13115–13118 (1993).
Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).
Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Matsubara, M., Saniz, R., Partoens, B. & Lamoen, D. Doping anatase TiO2 with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study. Phys. Chem. Chem. Phys. 19, 1945–1952 (2017).
Kokalj, A. Computer graphics and graphical user interfaces as tools in simulations of matter at the atomic scale. Comp. Mater. Sci. 28, 155–168 (2003).
Synthesis and physicochemical property analysis of the nanomaterial samples were supported by the Research Center Program of the IBS (IBS-R006-D1) in Korea (T.H.). Photocatalytic analysis was supported by the Creative Materials Discovery Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (NRF-2017M3D1A1039377). Computational work was supported by the Creative Materials Discovery Program (grant no. 2017M3D1A1039378) funded by the Korea government (MSIT). X-ray absorption spectroscopy work was supported by the Nano-Material Fundamental Technology Development programme (NRF-2018R1D1A1B07041997) through the NRF. The authors also thank the Korean Basic Science Institute (KBSI) at the Western Seoul Center for help with EPR measurements.
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Lee, BH., Park, S., Kim, M. et al. Reversible and cooperative photoactivation of single-atom Cu/TiO2 photocatalysts. Nat. Mater. 18, 620–626 (2019). https://doi.org/10.1038/s41563-019-0344-1
Copper-oxygen synergistic electronic reconstruction on g-C3N4 for efficient non-radical catalysis for peroxydisulfate and peroxymonosulfate
Separation and Purification Technology (2021)
Advanced Functional Materials (2021)
Designed synthesis of a porous ultrathin 2D CN@graphene@CN sandwich structure for superior photocatalytic hydrogen evolution under visible light
Chemical Engineering Journal (2021)
Recent advances in metals and metal oxides as catalysts for vanadium redox flow battery: Properties, structures, and perspectives
Journal of Materials Science & Technology (2021)
Nano Energy (2021)