Luminescence intensity corresponding to Eu3+ for SnO2:Eu3+ nanoparticles dispersed in Y2O3 increases significantly with increasing heat-treatment temperature up to 500 degrees C after excitation through exciton of SnO2. On further heat-treatment up to 900 degrees C, luminescence intensity decreases, whereas lifetime value for D-5(0) level of Eu3+ increases. This can be explained on formation of phases Y-2 xEuxSn2O7 and Y-2 yEuyO3 during heat-treatment. The former does not contribute to luminescence intensity, whereas the latter contributes to luminescence intensity. Availability of optically active Eu3+ ions decreases with heat-treatment and hence, luminescence intensity decreases. Enhancement of lifetime is related to homogeneous solid solution formation of Y-2 yEuyO3 during heat-treatment. (c) 2010 Elsevier B.V. All rights reserved.