Metal oxide nanoparticle ensembles are dynamic systems and can undergo a variety of chemical and structural transformation processes once they become exposed to water and other reactive environments. This contribution addresses aggregation induced formation of defects as well as dissolution-recrystallization processes nanoparticles synthesized in the gas-phase and made of simple metal oxides (MgO, TiO2, BaTiO3) can undergo. It will be shown that structure and microstructure evolution of metal oxide nanoparticle ensembles are subject to contact with water. These finding point also to simple and environmentally benign approaches to integrate morphologically well-defined nanoscale building blocks into larger high surface area materials.
 Metal Oxide Nanoparticles; Formation, Functional Properties, and Interfaces, Wiley VCH, ISBN: 9781119436744; Eds. O. Diwald and T. Berger, (2021), DOI:10.1002/9781119436782
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