PL and TL behaviors of Ag-doped SnO2 nanoparticles: effects of thermal annealing and Ag concentration

In this article, we present the effects of Ag doping and after-growth thermal annealing on the photoluminescence (PL) and thermoluminescence (TL) behaviors of SnO2 nanoparticles. SnO2 nanoparticles of 4-7 nm size range containing different Ag contents were synthesized by hydrothermal process. It has been observed that the after-growth thermal annealing process enhances the crystallite size and stabilizes the TL emissions of SnO2 nanostructures. Incorporated Ag probably occupies the interstitial sites of the SnO2 lattice, affecting drastically their emission behaviors on thermal annealing. Both the TL response and dose-linearity of the SnO2 nanoparticles improve on 1.0% Ag doping, and subsequent thermal annealing. However, a higher Ag content causes the formation of Ag clusters, reducing both the TL and PL responses of the nanoparticles.