Abstract
Surfaces decorated with uniformly dispersed catalytically active nanoparticles play a key role in many fields, including renewable energy and catalysis. Typically, these structures are prepared by deposition techniques, but alternatively they could be made by growing the nanoparticles in situ directly from the (porous) backbone support. Here we demonstrate that growing nano-size phases from perovskites can be controlled through judicious choice of composition, particularly by tuning deviations from the ideal ABO3 stoichiometry. This non-stoichiometry facilitates a change in equilibrium position to make particle exsolution much more dynamic, enabling the preparation of compositionally diverse nanoparticles (that is, metallic, oxides or mixtures) and seems to afford unprecedented control over particle size, distribution and surface anchorage. The phenomenon is also shown to be influenced strongly by surface reorganization characteristics. The concept exemplified here may serve in the design and development of more sophisticated oxide materials with advanced functionality across a range of possible domains of application.
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Change history
08 October 2013
In the version of this Article originally published online, two references to panels in Fig. 4 were incorrect: In the caption for Fig. 4g in “Sample f aged in 3%H2O/5%H2/Ar…”, it should have read ‘Sample e’. In the last paragraph of the section ‘Influence of stoichiometry on surface morphology’, in “… by reducing some of the decorated surfaces (for example, see Fig. 4c)…” it should have read ‘4e’. These errors have been corrected in all versions of the Article.
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Acknowledgements
The authors thank the Engineering and Physical Sciences Research Council, Supergen XIV Project Delivery of Sustainable Hydrogen (EP/G01244X/1), and the European Project METSAPP (FCH JU-GA 278257) for funding.
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D.N. and J.T.S.I. conceived and designed the experiments and analysed the data. D.N. performed the experiments with assistance from G.T. who also contributed to data analysis. D.N.M. collected and interpreted the HRTEM data, and H.M. collected and interpreted the XPS data. D.N. drafted the manuscript and all authors commented on it.
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Neagu, D., Tsekouras, G., Miller, D. et al. In situ growth of nanoparticles through control of non-stoichiometry. Nature Chem 5, 916–923 (2013). https://doi.org/10.1038/nchem.1773
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DOI: https://doi.org/10.1038/nchem.1773