Near -infrared photoluminescence and phosphorescence properties of Cr 3+-Doped garnet -type Y 3 Sc 2 Ga 3 O 12

Garnet-type Y₃Sc₂Ga₃O₁₂:Cr³⁺ phosphor has been synthesized by a solid-state reaction. XRD result revealed the successful phase formation and Cr³⁺ doping in Y₃Sc₂Ga₃O₁₂. The excitation spectrum at about 260, 450, and 630 nm corresponded to three spin-allowed Cr³⁺ d-d intra-transitions of ⁴A₂-⁴T₁ (⁴P), ⁴A₂-⁴T₁ (⁴F), and ⁴A₂-⁴T₂ (⁴F), respectively, among which the near infrared (NIR) emission peak at around 740 nm is identified. Moreover, the phosphorescence emission property, thermoluminescence and related luminescence mechanisms are discussed as well. The fabricated NIR phosphor-converted light-emitting diodes (pc-LEDs) suggest its potential of Y₃Sc₂Ga₃O₁₂:Cr³⁺ phosphor for non-visible light source application.