Mn-Activated Fluoride Phosphors Modified by Surfactant with Outstanding Water Resistance and Luminescent Thermal Properties
Lin Wang, Daishu Deng, Jiawei Qiang, Jun Lei, Tianman Wang, Yuelan Li, Sen Liao, Yingheng Huang
Abstract
Although Mn 4+ -activated fluoride phosphors have high luminescence quality, their poor water resistance and thermal fluorescence properties significantly limit their practical applications. Here, we propose a surfactant modification strategy by adding the surfactant cetyltrimethylammonium bromide (CTAB) to the synthesis and modifying the surface of the phosphor with ethylene diamine tetraacetic acid (EDTA) to obtain a phosphor with excellent luminescence thermal properties and water resistance, K 2 TiF 6:Mn 4+ - x CTAB-EDTA (KTFM- x C-E) phosphors. The experimental and X-ray diffraction Rietveld refinement results confirm that the phosphor has higher structural rigidity and thus improved thermal stability. The surface modification with EDTA resulted in the formation of a dilute Mn 4+ shell layer on the phosphor surface, which prevented the inward hydrolysis of the phosphor and resulted in excellent water resistance. Therefore, we have successfully modified K 2 TiF 6:Mn 4+ (KTFM) phosphors using low-cost surfactants, which also provides new ideas for other commercial high-quality phosphors.