Erbium-induced blurring of the fractal surface of SnO2 nanocrystals grown in silica

摘要

We show here what kind of modification of the interphase morphology of SnO2 nanoparticles in silica (average nanocrystal radius, $hat{r}approx 4,hbox{nm}$ in undoped material; $hat{r},approx,2,hbox{nm}$ in erbium doped material) brings to the passivation of interfacial defects. Surface states, which may preclude the exploitation of UV excitonic emission, are reduced after doping by rare earth ions. We demonstrate, by means of transmission-electron-microscopy and small-angle-neutron-scattering data, that a smooth interphase with a non negligible thickness takes the place of the fractal and discontinuous boundary observed in undoped material.