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Structural transformations of solid electrocatalysts and photocatalysts

Abstract

Heterogeneous catalysts often undergo structural transformations when they operate under thermal reaction conditions. These transformations are reflected in their evolving catalytic activity, and a fundamental understanding of the changing nature of active sites is vital for the rational design of solid materials for applications. Beyond thermal catalysis, both photocatalysis and electrocatalysis are topical because they can harness renewable energy to drive uphill reactions that afford commodity chemicals and fuels. Although structural transformations of photocatalysts and electrocatalysts have been observed in operando, the resulting implications for catalytic behaviour are not fully understood. In this Review, we summarize and compare the structural evolution of solid thermal catalysts, electrocatalysts and photocatalysts. We suggest that well-established knowledge of thermal catalysis offers a good basis to understand emerging photocatalysis and electrocatalysis research.

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Fig. 1: Structural transformation of solids during thermal catalysis.
Fig. 2: Structural changes of supported metal catalysts during CO oxidation.
Fig. 3: Changes in morphology and surface structure of metal nanoparticles.
Fig. 4: Structural transformation of perovskite catalysts during the OER.
Fig. 5: Structure evolution of Co(2-methylimidazolate)2 during electrocatalytic oxygen evolution.
Fig. 6: Cooperative photoactivation cycle of a Cu–TiO2 catalyst featuring isolated Cu sites.
Fig. 7: Structural evolution of solid photocatalysts.

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Acknowledgements

We are grateful for the financial supports from the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the ‘Severo Ochoa Program’ (SEV-2016-0683).

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A.C. conceived the structure of this Review. L.L. and A.C. wrote this Review together.

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Correspondence to Avelino Corma.

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Liu, L., Corma, A. Structural transformations of solid electrocatalysts and photocatalysts. Nat Rev Chem 5, 256–276 (2021). https://doi.org/10.1038/s41570-021-00255-8

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