V2O5-SnO2 double-shelled nanocapsules and their formation process. (a) Schematic presentation of the formation process of V2O5-SnO2 double-shelled nanocapsules based on Ostwald ripening. (b) SEM image of V2O5-SnO2 double-shelled nanocapsules. Inset shows the schematic structure of these double-shelled nanocapsules. (c-e) TEM images indicate that the porous shell consists of a great deal of nanocrystals. (f-h) HRTEM images revealing lattice planes of the V2O5 matrix and SnO2 nanocrystals. (i) SAED pattern taken from individual nanocapsules which shows that these nanocapsules are polycrystalline. Adapted from  and reproduced with the permission of the American Chemical Society.
Liu et al. Nanoscale Research Letters 2012 7:149 doi:10.1186/1556-276X-7-149