Novel Sm3+-activated YCa4O(BO3)3 phosphors with high quantum efficiency and thermal stability for red-backlight display and indoor illumination

Novel Sm3+-activated YCa4O(BO3)3 (YCOB) phosphors with high color purity, excellent thermal stability and high luminescence quantum efficiency were developed. Upon 405 nm excitation, all samples displayed strong orange-red emissions. The crystal structure and luminescence characteristics of YCOB in relation to Sm3+ concentrations were explored. The optimal doping concentration was found to be 5% mol with remarkable color purity of 97.73%. The concentration quenching mechanism in YCOB host lattices was dominated by dipole-dipole interaction. Meanwhile, temperature-dependent luminescence spectra revealed that the investigated phosphors have excellent thermal stability. Impressively, it was calculated that the internal quantum efficiency of synthesized phosphors was as high as 76.54%. To further verify the practicability of synthesized phosphors, both red light-emitting diodes and white light-emitting diodes were fabricated using YCOB: 5%Sm3+ phosphors, and they exhibited bright red and white light, respectively. These results suggest that the novel YCOB: Sm3+ phosphors with high quantum efficiency and luminescent stability were promising for red-backlight display and indoor illumination.