Color-tunable photoluminescence and energy transfer of (Tb 1- x Mn x ) 3 Al 2 (Al 1- x Si x ) 3 O 12 :Ce 3+ solid solutions for white light emitting diodes.

(Tb 1- x Mn x ) 3 Al 2 (Al 1- x Si x ) 3 O 12 :Ce 3+ solid solution phosphors were synthesized by introducing the isostructural Mn 3 Al 2 (SiO 4 ) 3 (MAS) into Tb 3 Al 5 O 12 :Ce 3+ (TbAG). Under 456 nm excitation, (Tb 1- x Mn x ) 3 Al 2 (Al 1- x Si x ) 3 O 12 :Ce 3+ shows energy transfers (ET) in the host, which can be obtained from the red emission components to enhance color rendering. Moreover, (Tb 1- x Mn x ) 3 Al 2 (Al 1- x Si x ) 3 O 12 :Ce 3+ ( x = 0-0.2) exhibits substantial spectral broadening (68 → 86 nm) due to the 5d → 4f transition of Ce 3+ and the 4 T 1 → 6 A 1 transition of Mn 2+ . The efficiency of energy transfer ( η T , Ce 3+ → Mn 2+ ) gradually increases with increasing Mn 2+ content, and the value reach approximately 32% at x = 0.2. Namely, the different characteristics of luminescence evolution based on the effect of structural variation by substituting the (MnSi) 6+ pair for the larger (TbAl) 6+ pair. Therefore, with structural evolution, the luminescence of the solid solution phosphors could be tuned from yellow to orange-red, tunable by increasing the content of MAS for the applications of white light emitting diodes (wLED).