Realization of color tunable via energy transfer in Ba1.2Ca0.8SiO4:Tb3+, Mn2+ phosphor

Highlights: • Tb³⁺/Mn²⁺ doped T-phase orthosilicate Ba_1.2Ca_0.8SiO₄ phosphors were synthesized. • Emission intensity of Mn²⁺ for BCS:Tb³⁺,Mn²⁺ is enhanced than that of BCS:Mn²⁺. • Energy transfer mechanism is confirmed based on I–H model and Dexter's theory. • Emission color of BCS:Tb³⁺,Mn²⁺ can be tuned from green to red-orange. -- Abstract: A detailed investigation on photoluminescence properties and energy transfer mechanism of Tb³⁺/Mn²⁺ singly doped and co-doped T-phase orthosilicate Ba_1.2Ca_0.8SiO₄ (BCS) phosphors, synthesized by conventional solid state reaction, is provided. All the samples were investigated by X-ray diffraction (XRD), photoluminescence spectroscopy and fluorescence decay curve. The Mn²⁺ emission intensity of BCS:Tb³⁺, Mn²⁺ is 28 times stronger than that of BCS:Mn²⁺. In addition, the emission color of BCS:Tb³⁺, Mn²⁺ phosphors can be tuned from green to orange-red by varying Mn²⁺ concentration. The efficient energy transfer from Tb³⁺ to Mn²⁺ is responsible for these phenomena. By employing the Inokuti–Hirayama model and Dexter's energy transfer theory, the dipole–dipole interaction is confirmed as the predominant multipolar effect in controlling this energy transfer process.