Zhong Xue, Deng Daishu, Wang Tianman, Li Yuelan, Yu Yan, Qiang Jiawei, Liao Sen, Huang Yingheng, Long Jinqiao
School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, China.
School of Resources, Environment and Materials, Guangxi University, Nanning, Guangxi 530004, China.
Inorg Chem. 2022 Apr 11;61(14):5484-5494. doi: 10.1021/acs.inorgchem.1c03488. Epub 2022 Mar 29.
Mn-doped fluoride phosphors are efficient narrowband red-emitting phosphors for white light-emitting diodes (WLEDs) and backlight displays. However, erosion by moisture is the main obstacle that limits their application. In this work, LNSF:Mn (LiNaSiMnF) with high quantum yield (QY), luminescent thermal stability, and waterproofness was synthesized using the HO-free reaction method at room temperature. Compared to NSF:Mn(NaMnSiF), the QY value, luminescence thermal stability, and water resistance of LNSF:Mn are obviously improved by codoping of Li because of the formation of charge-carrier transfer (CT) and rare-Mn layer induced by codoping of Li. The former produces the negative thermal quenching (NTQ) effect, which results in the improvement of the luminescent thermal stability. The latter can inhibit the hydrolysis of Mn on the surface of the sample, which leads to the enhancement of waterproofness. The formation mechanism of the rare-Mn layer is discussed. A prototype WLED emitting the ideal warm white light (CCT = 3173 K, = 90.4) was assembled by coating a mixture of LNSF:Mn, yellow emitting phosphor (YAG:Ce), and epoxy resin on the blue light InGaN chip, indicating that the performance of the WLED can be improved by using LNSF:Mn.
锰掺杂氟化物荧光粉是用于白光发光二极管（WLED）和背光显示器的高效窄带红色发光荧光粉。然而，水分侵蚀是限制其应用的主要障碍。在这项工作中，采用无HO反应法在室温下合成了具有高量子产率（QY）、发光热稳定性和防水性的LNSF:Mn（LiNaSiMnF）。与NSF:Mn(NaMnSiF)相比，由于锂共掺杂形成了电荷载流子转移（CT）和稀土锰层，LNSF:Mn的QY值、发光热稳定性和耐水性明显提高。前者产生负热猝灭（NTQ）效应，从而提高了发光热稳定性。后者可以抑制样品表面锰的水解，从而提高防水性。讨论了稀土锰层的形成机理。通过在蓝光InGaN芯片上涂覆LNSF:Mn、黄色发光荧光粉（YAG:Ce）和环氧树脂的混合物，组装了发出理想暖白光（CCT = 3173 K， = 90.4）的WLED原型，表明使用LNSF:Mn可以提高WLED的性能。
