Long persistent luminescence property of a novel green emitting SrLaGaO4: Tb3+ phosphor

A novel long persistent green emitting phosphor SrLaGaO4: Tb3+ was synthesized via a conventional high temperature solid-state method. The obtained results indicated that the green long persistent emitting was similar to the photoluminescence, originating from the f-f transitions of Tb3+ centers which were supposed to occupy the random distribution Sr2+ and La3+ sites. The duration of green afterglow can be observed in the dark by naked eyes even after more than 3.5 h. The thermoluminescence results revealed that SrLaGaO4: Tb3+ possessed three main traps calculated to be 0.62, 0.68 and 0.77 eV, which were responsible for the long persistent green luminescence. The further structure analysis revealed that the Tb3+ dopants not only acted as emission centers but also significantly influenced the density of traps, and the trapping centers were postulated nonrandom distribution under the assistance of high temperature, which resulted in the efficient persistent luminescence of Tb3+. All the results showed that SrLaGaO4: Tb3+ was a potential long persistent luminescent material.