In exsolution, nanoparticles form by emerging from oxide hosts by application of redox driving forces, leading to transformative advances in stability, activity, and efficiency over deposition techniques, and resulting in a wide range of new opportunities for catalytic, energy and net-zero-related technologies. However, the mechanism of exsolved nanoparticle nucleation and perovskite structural evolution, has, to date, remained unclear. Herein, we shed light on this elusive process by following in real time Ir nanoparticle emergence from a SrTiO3 host oxide lattice, using in situ high-resolution electron microscopy in combination with computational simulations and machine learning analytics. We show that nucleation occurs via atom clustering, in tandem with host evolution, revealing the participation of surface defects and host lattice restructuring in trapping Ir atoms to initiate nanoparticle formation and growth. These insights provide a theoretical platform and practical recommendations to further the development of highly functional and broadly applicable exsolvable materials.
|State||Published - Dec 2023|
Bibliographical noteFunding Information:
This work was performed as part of the Engineering and Physical Science Research Council grant numbers EP/R023522/1, and EP/R023603/1. The in situ STEM research was supported by the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory, which is a US Department of Energy Office of Science User Facility, and this work was supported in part by the National Science Foundation under DMR 1455154 (M.P.T., B.S.G.). J.W. and S.C.P. gratefully acknowledge support from the ARCHER2 UK National Supercomputing Service and YOUNG HPC (supported by the UK Materials and Molecular Modelling Hub, which is partially funded by EPSRC (EP/T022213)) for providing computation resources, accessed through the U.K. Materials Chemistry Consortium (funded by the EPSRC grants: EP/R029431). The authors are grateful to all the members of the Emergent Nanomaterials (EPSRC Critical Mass Proposal) project for useful discussion.
© 2023, The Author(s).
ASJC Scopus subject areas
- Physics and Astronomy (all)
- Chemistry (all)
- Biochemistry, Genetics and Molecular Biology (all)