Effect of Sr~(2+)-doping on structure and luminescence properties of BaAl_(2)Si_(2)O_(8):Eu~(2+) phosphors

摘要

Sr~(2+) doped BaAl_(2)Si_(2)O_(8):Eu~(2+) phosphor was synthesized by chemical co-precipitation method. With the increase of Sr~(2+) concentration, the phase structure of (Ba_(0.965-x)Sr_(x)Eu_(0.035))Al_(2)Si_(2)O_(8) changes from hexagonal phase to monoclinic phase owing to large activation energy in SrAl_(2)Si_(2)O_(8) system. (Ba_(0.965-x)Sr_(x)Eu_(0.035)) Al_(2)Si_(2)O_(8) phosphor exhibits a broad blue band peaking at 425 nm due to the 4f~(6)5d-4f~(7)(~(8)S_(7/2)) transition of Eu~(2+) ions. The emission intensity increases, accompanied by the blue shift of emission maximum from 459 to 417 nm with the Sr~(2+) doping concentration increasing. The optimal concentration of Sr~(2+) ion is 40percent, and the phosphor shows high color stability in CIE chromaticity diagram. The result indicates that Sr~(2+) doped phosphor not only can enhance the relative intensity but also can adjust the chromaticity coordinate.