Photoluminescence and preparation of ZnNb2O6 doped with Eu3+ and Tm3+ nanocrystals for solar cell

Synthesis and luminescence properties of Eu3+ and Tm3+-doped ZnNb2O6 nanocrystals by the sol–gel process were investigated. The products were characterized by differential thermal analysis (DTA), scanning electron microscopy (SEM), and photoluminescence spectroscopy (PL). ZnNb2O6:Eu3+ shows bright red luminescence with maximum peak at 613 nm attributed to 5D0 → 7F2 transition. The major blue emission peak of ZnNb2O6:Tm3+ was at 483 nm, corresponding to the transitions 1G4 → 3H6. The optimum concentration of Eu3+ and Tm3+ showing the maximum PL intensity was 4 mol% and 1 mol%, respectively.