Pyrophosphate Phosphor Solid Solution with High Quantum Efficiency and Thermal Stability for Efficient LED Lighting.

Phosphors with high quantum efficiency and thermal stability are greatly desired for lighting industries. Based on the design strategy of solid solution, a series of deep-blue-emitting phosphors (Sr(0.99-x)Ba(x))(2)P(2)O(7):0.02Eu(2+) (SB(x)PE x = 0-0.5) are developed. Upon excitation at 350 nm, the optimized SB(0.3)PE phosphor shows a relatively narrow full width at half maximum (FWHM = 32.7 nm) peaking at 420 nm, which matches well with the plant absorption in blue region. Moreover, this phosphor exhibits obvious enhancement of internal quantum efficiency (IQE) (from 74% to 100%) and thermal stability (from 88% to 108% of peak intensity and from 99% to 124% of integrated area intensity at 150°C) compared with the pristine one. The white LED devices using SB(0.3)PE as deep-blue-emitting component show good electronic properties, indicating that SB(0.3)PE is promising to be used in plant growth lighting, white LEDs, and other photoelectric applications.