The greenish-blue emission and thermoluminescent properties of CaTa2O6:Pr3+

Graphical abstract: A greenish-blue glowing Pr3+ emission was observed from the rare 3P0 → 3H4 transition from CaTa2O6:Pr3+ phosphor. Electron stimulation from the electron trapping centers of the phosphor obeys neither first nor second order kinetics. Highlights: • A greenish-blue glowing CaTa2O6:Pr3+ phosphor was prepared. • Major Pr3+ emission was observed from the rare 3P0 → 3H4 transition. • Competition between three different electron trapping centres of the phosphor was observed. • Electronic trap displacement as a result of pre dosing, was observed. • The energy distribution of electron trapping centers was calculated. -- Abstract: Pr3+ exhibits prominent red emission in most oxide phosphors, which comes from the 1D2 → 3H4 transition, and greenish-blue emission from 3P0 → 3H4,5 transitions is normally less intense. However, a greenish-blue emission was observed from CaTa2O6:Pr3+ oxide phosphor prepared by solid state reaction at 1200 °C. A combination of emission coming from 1D2 and 3P0 levels was observed, with the blue emission from the latter much more prominent. Upon investigating the thermoluminescence properties of the phosphor, the glow curves showed the presence of three different types of electron trapping centres. Interesting properties of the trapping centres, such as the competition between the trapping centres, pre-radiation effects and the calculation of the activation energy were studied. The phosphorescence decay curves showed long lasting afterglow