Deep red emitting Mg2La2SnO7:Mn4+ phosphor: Synthesis and luminescence properties

Mg 2 La 2 SnO 7 :Mn 4+ phosphor is synthesized by the solid-state reaction method in air. Monitored at 706 nm, excitation spectrum of Mg 2 La 2 SnO 7 :Mn 4+ phosphor including peaks at ∼ 300, 333, 395, and 516 nm can be observed in the range of 220–600 nm. With excitation at 333 nm, emission band of Mg 2 La 2 SnO 7 :Mn 4+ phosphor is shown in the range of 640–780 nm owing to the 2 E → 4 A 2 transitions of Mn 4+ ion. The optimal Mn 4+ ion concentration is ∼ 0.3 mol% in Mg 2 La 2 SnO 7 :Mn 4+ phosphor. The lifetime decreases from 1.23 to 0.83 ms with the increase of Mn 4+ concentration from 0.1 to 1.2 mol%. There is only one luminescence center (Mn 4+ ) in Mg 2 La 2 SnO 7 :Mn 4+ phosphor, which is confirmed by the luminescence properties, decay curves, and time-resolved emission spectra. Mg 2 La 2 SnO 7 :Mn 4+ phosphor has good thermal stability. Luminous mechanism is explained by energy level diagram of Mn 4+ ion and the thermal quenching phenomenon is analyzed by the configuration coordinate diagram of Mn 4+ ion.