Local Structure Modulation-Induced Highly Efficient Red-Emitting BaGdYNbO:Mn Phosphors for Warm WLEDs.

Modulating the crystal field environment around the emitting ions is an effective strategy to improve the luminescence performance of the practical effective phosphor materials. Here, smaller Y ions are introduced into substituting the Gd sites in BaGdNbO:Mn phosphor to modify the optical properties, including the enhanced luminescence intensity, redshift, and longer lifetime of the Mn ions. The substitution of smaller Y ions leads to lattice contraction and then strengthens pressure on the local structure, enhances lattice rigidity, and suppresses nonradiative transition. Moreover, the prototype phosphor-converted light-emitting diode (LED) demonstrates a continuous change photoelectric performance with a correlated color temperature of 4883-7876 K and a color rendering index of 64.1-83.2, suggesting that it can be one of the most prospective fluorescent materials applied as a warm red component for white LEDss. Thus, the smaller ion partial substitution can provide a concise approach to modulate the crystal field environment around the emitting ions for excellent luminescence properties of phosphors toward the modern artificial light.