Ajuts: CSIC/CNR project 2010IT0001 (SYNCAMON), SOLAR project DM19447, VINNOVA Marie Curie Incoming Grant under "Light Energy" project.

SnO nanocrystals were prepared by precipitation in dodecylamine at 100 °C, then they were reacted with vanadium chloromethoxide in oleic acid at 250 °C. The resulting materials were heat-treated at various temperatures up to 650 °C for thermal stabilization, chemical purification and for studying the overall structural transformations. From the crossed use of various characterization techniques, it emerged that the as-prepared materials were constituted by cassiterite SnO nanocrystals with a surface modified by isolated V(IV) oxide species. After heat-treatment at 400 °C, the SnO nanocrystals were wrapped by layers composed of vanadium oxide (IV-V mixed oxidation state) and carbon residuals. After heating at 500 °C, only SnO cassiterite nanocrystals were obtained, with a mean size of 2.8 nm and wrapped by only V O-like species. The samples heat-treated at 500 °C were tested as RhB photodegradation catalysts. At 10 M concentration, all RhB was degraded within 1 h of reaction, at a much faster rate than all pure SnO materials reported until now.