Visible to infrared low temperature luminescence of Er³⁺, Nd³⁺ and Sm³⁺ in CaSnO₃ phosphors

Novel stannate phosphor, orthorhombic CaSnO₃ phosphors doped with Er³⁺, Nd³⁺ and Sm³⁺ have been synthesized by a conventional solid-state method under N₂+H₂ gas flow. Visible and near-infrared photoluminescence (PL) properties were investigated as function of laser power and temperature. It was observed that all dopant ions are well incorporated in CaSnO₃ and are responsible for the optical emission in the temperature range of 10–300 K. PL peaks at 490, 546, 656, 696, 894, 1065, and 1344 nm were observed for the CaSnO₃:Nd³⁺ phosphor and associated to f–f transition of Nd³⁺ ion. Emissions at 564, 600–607, 646–656 and 714 nm were detected for the CaSnO₃:Sm³⁺. The strongest one, observed at 600 nm, was associated to ⁴G_5/2→⁶H_7/2 of Sm³. Emission lines at 528, 548, 662 at 852 nm were also seen for CaSnO₃:Er³⁺ and correspond to Er³⁺ intra-4fⁿ shell transitions. In addition, at low temperatures, a stark splitting of the 4f electron energy levels of the Er³⁺ ions were observed in infrared region (1520–1558 nm) and assigned to the transition between the ⁴I_13/2 state and the ⁴I_15/2 state. Finally, our results show that the rare earth doped CaSnO₃ has remarkable potential for applications as optical material since it exhibits efficient and sharp emissions due to rare earth ions. - Highlights: • Characteristic and photoluminescence properties have been investigated. • Several sharp and strong emission bands due to rare earth ions were observed. • The nature of the interaction between host and the activator ions were discussed