Spectral modulation of BCNO phosphors by Al3+ and Ti4+ doping for white LEDs

BCNO phosphors with Al3+ and Ti4+ doping were synthesized and their spectral properties were systematically investigated. The BCNO phosphors with Al3+ doping are mainly composed of amorphous Al2O3 and BCNO nanocrystal. The crystallinity of BCNO phosphors and intensity of B-N related chemical bonds are improved with Al3+ doping which leads to the enhancement of quantum yields from 5.6% to 63.4%. In addition, The BCNO phosphors with Ti4+ doping are consisted of TiO2 with anatase and rutile structures and BCNO nanocrystals. The emission spectra are red shifted from 510 nm to 555 nm with the increase of Ti4+ doping, and the excitation intensity is successfully improved by Ti4+ doping in a wide range of 400−500 nm, which is favorable for blue light excitation. Both the spectral properties and electron transition process can be explained by a simplified energy band diagram. The BCNO phosphors with Al3+ and Ti4+ doping can be good candidates for white LED with ultraviolet and blue light excitation.