[EN] Hexagonal (W,V)O3−x oxides of high thermal stability have been synthesized hydrothermally through the
intermediate products Nax(W,V)O3·zH2O and (NH4)0.33−x(W,V)O3−y. The obtained crystals show nanostructured
surface via the formation of a dense population of polyhedral nanocavities self-distributed
along particular crystallographic directions. Nanocavities present a regular size that ranges from 5 to
10 nm in both length and width. The synthesis process involves a significant topotactic relationship
between the as-synthesized product and the desired final product and this relationship is suggested as
the origin of the observed surface nanostructure. The comparison of our results with observations in
different solids has allowed us to suggest that the formation of nanocavities is an extensive spontaneous
process when materials are obtained by the chemical reactions of solids leading to products with defined
crystallographic orientation with respect to the original compound. The characterization provides evidence
regarding the potential relevance of nanocavities in the functional properties of the resulting solids.Authors acknowledge the financial support from DGICYT in Spain through projects MAT2010-19837-C06-05 and CTQ2012-37925-C03-1. Authors are also grateful to the Centro de Microscopia Electronica (UCM) for facilities.García-González, E.; Soriano Rodríguez, MD.; Urones-Garrote, E.; López Nieto, JM. (2014). On the Origin of the Spontaneous Formation of Nanocavities in Hexagonal Bronzes (W,V)O3. Dalton Transactions. 43:14644-14652. https://doi.org/10.1039/C4DT01465KS14644146524
