Investigation of structure and luminescence properties of Tb3+ activated Gd(Ta1−xPx)O4 phosphors

Highlights: • The influence of mixed matrix related to Gd(Ta_1-xP_x)O₄ phosphors was investigated. • The structures and luminescence properties of the phosphors were analyzed. • The optimal doping concentration is x = 0.1 and y = 10, respectively. • Color-tunable emission in yellowish-green range can be obtained. Gd(Ta_1−xP_x)O₄: y at.% Tb³⁺ phosphors with various doping concentrations of (PO₄)³⁻ and Tb³⁺ were prepared through high temperature solid-state method, and the corresponding crystal structures and luminescence properties were explored. XRD results indicate single phase M-Gd (Ta_1-xP_x) O₄ can be obtained with 1300 °C sintering conditions without phase transformation. The optimized doping concentration for ${\left({\text{PO}}_4\right)}^{3-}\text{and}{\left({\text{TaO}}_4\right)}^{3-}$ in M-type Gd(Ta_1-xP_x)O₄: y at.% Tb³⁺ is x = 0.1 and y = 10 to obtain maximum luminous intensity, respectively. Moreover, the luminescence decay time of Tb³⁺ ions in Gd(Ta_0.9P_0.1)O₄ matrix under optimized doping condition is about 1 ms and CIE chromaticity results imply the phosphors exhibit yellowish-green emission. These results suggest the Gd(Ta_1−xP_x)O₄: y at.% Tb³⁺ phosphors are promising candidates for LED luminescence or medical imaging applications.