Tunable Blue-to-Orange-Red Emission in LaPO4: Sb3＋/Mn2＋ Phosphors: Multiple emission centers for LED applications

Abstract

This study explores synthesizing and characterizing LaPO 4 :Sb 3＋ / (LSBMx) phosphors (x = 0%–5%) prepared via the co-precipitation method. Structural analysis and luminescence properties reveal that LSBM0 (without Mn 2＋ ) emits blue light under UV excitation, while Mn 2＋ -doped samples exhibit tunable emission from blue to orange-red. Under UV excitation, LSBMx phosphors demonstrate a broad visible emission band with multiple peaks attributed to the transition of Mn 2＋ . The broad emission band (520 – 660 nm) can be deconvoluted into four Gaussian components centered at 564 nm (Mn-I), 595 nm and 616 nm (Mn-II), and 648 nm (Mn-III), corresponding to Mn 2＋ in La 3＋ sites due to charge inconsistency, crystal field modifications induced by Sb 3＋ incorporation, and Mn 2＋ - Mn 2＋ dimers, respectively. Energy transfer efficiency calculations determine the optimal Mn 2＋ concentration to be approximately 3%. This novel phosphor system demonstrates versatile green, orange, and red emission capabilities, establishing a valuable framework for developing Mn 2＋ -doped luminescent materials with potential applications in LED lighting technology.