Effects of annealing temperature and ambient atmosphere on the structure and photoluminescence of BCNO phosphors

A facile strategy based on the reaction of urea, boric acid and polyethylene glycol is used for the synthesis of toxicity-free BCNO phosphor. The structure and luminescent properties of samples annealed under various ambient atmospheres and different annealing temperatures are investigated in detail. The annealed BCNO phosphors have a t-BN crystalline structure mixing mainly with cubic B2O3. The crystallinity quality of BCNO phosphors is improved as the annealing temperature increases. The photoluminescent intensity is related to the crystallinity and the main emission peak shifts from 530 nm to the two bands of 325-350 nm and 400-450 nm, respectively. In addition, vibration modes vary with annealing temperatures and ambiences.