Tunable white light emission through energy transfer processes between silver species in Ag-doped zinc phosphate glass

Abstract

Silver doped zinc phosphate glass was successfully synthesized at different molar concentrations of AgCl from 1% up to 20%. Zinc phosphate glass shows a high capacity to hold silver impurities without loss of optical quality. This material shows two different centers able to emit blue and green-red light, the first one from isolated Ag+ ions and the latter from Ag+ pairs. The intensity of each emission can be tuned by varying the composition of silver in the matrix, reaching the white light emission at 12 and 14% molar AgCl. Two energy transfer mechanisms were detected: charge transfer from zinc phosphate glass matrix to isolated Ag+ ions (that can improve the forbidden blue emission) and energy transfer from Ag+ single ions to Ag+ pairs.