Optimizing interstitial site luminescence via a sensitizer strategy towards green synthesis of Mn 4+ -activated fluoride phosphors

作者：Xintong Yao, Lingyu Kong, Gaoxuanyu Guan, Yuping Hu, Rui Luo, Qiannan Li, Tianchun Lang, Tao Han, Bitao Liu · 发表于：Physica Scripta · 年份：2023 · DOI：10.1088/1402-4896/acfc00 · 研究领域：Luminescence Properties of Advanced Materials、Inorganic Fluorides and Related Compounds、Ga2O3 and related materials

Abstract High water-soluble KHF 2 :Mn 4+ (KHFM) is a potential precursor instead of K 2 MnF 6 for preparation of Mn 4+ doped fluoride materials, but it has a lower Mn 4+ concentration in precursor causing a poor luminescence performance. Herein, we reported a Ti 4+ -doped KHFM phosphor with high luminous efficiency, high thermal stability via a sensitizer strategy. Significantly, the luminescence intensity of KHFM:xTi 4+ (x = 0.8%) is increased by 4.6 times, besides, the maximum values of the internal quantum efficiency (IQE) and external quantum efficiency (EQE) increased to 81% and 49%, respectively. Further, the weaker zero phonon line (ZPL) at 621 nm (1.997 eV) is accordingly highlighted with the increase of PL intensity after codoping Ti 4+ content. These results indicate that introducing suitable ion to interstitial site as sensitizer can promote the introduction of Mn 4+ in ion exchange process. Notably, the obtained KHFM:Ti 4+ , as a particular green precursor material instead of K 2 MnF 6 , develops a novel green synthetic route for preparing Mn 4+ -activated K 2 SiF 6 fluoride phosphors, and is helpful in developing high-performance warm WLED.