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Water‐Mediated Surface Diffusion Mechanism Enables the Cold Sintering Process: A Combined Computational and Experimental Study
Author(s) -
Sengul Mert Y.,
Guo Jing,
Randall Clive A.,
van Duin Adri C. T.
Publication year - 2019
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201904738
Subject(s) - sintering , reaxff , surface diffusion , recrystallization (geology) , materials science , adsorption , grain growth , chemical engineering , ceramic , molecular dynamics , diffusion , oxide , nanocrystal , nanocrystalline material , crystallization , chemical physics , grain size , metallurgy , thermodynamics , chemistry , nanotechnology , computational chemistry , paleontology , physics , interatomic potential , engineering , biology
The cold sintering process (CSP) densifies ceramics at much lower temperatures than conventional sintering processes. Several ceramics and composite systems have been successfully densified under cold sintering. For the grain growth kinetics of zinc oxide, reduced activation energies are shown, and yet the mechanism behind this growth is unknown. Herein, we investigate these mechanisms in more detail with experiments and ReaxFF molecular dynamics simulations. We investigated the recrystallization of zinc cations under various acidic conditions and found that their adsorption to the surface can be a rate‐limiting factor for cold sintering. Our studies show that surface hydroxylation in CSP does not inhibit crystallization; in contrast, by creating a surface complex, it creates an orders of magnitude acceleration in surface diffusion, and in turn, accelerates recrystallization.