A New Strategy to Improve the Thermal Stability of (Sr, Ba)2sio4: Eu2+ Phosphors by Ion Substitution Engineering

作     者：Liu, Zhengqiang Seto, Takatoshi Tian, Houdao Wang, Yuhua 

作者机构：National and Local Joint Engineering Laboratory for Optical Conversion Materials and Technology of National Development and Reform Commission School of Materials and Energy Lanzhou University Lanzhou730000 China 

出 版 物：《SSRN》 

年 卷 期：2022年

核心收录：

主　　题：Phosphors 

摘      要：With high quantum efficiency and appropriate excitation & emission wavelength, (Sr, Ba)2SiO4: Eu2+ phosphors exhibit perfect photoluminescence properties in the room temperature. However, limited by its poor thermal stability, they are difficult to be applicated in the high-performance lighting and display fields. In this work, we propose a new strategy of ion substitution engineering to greatly improve the thermal stability of (Sr, Ba)2SiO4: Eu2+ phosphors. Through the conventional high-temperature solid-state reaction, we successfully introduced alkali metal ions K+/Na+ into the SrBaSiO4 host lattice, thereby strengthening its structural rigidity, and improving the luminous intensity and narrowing the Full-Width Half-Maximum (FWHM) of the phosphors. The substitution of K+/Na+ ions can also deepen the traps in the phosphor, which proved by the thermoluminescence (TL) measurement. Joint effect of the stronger crystal rigidity and deeper traps leads to a higher thermal stability, and the emission intensity at 150 °C can reach to 81.5% of the room temperature with Na+ substitution, which is significantly better than the commercial SrBaSiO4: Eu2+ phosphor. The mechanism of alkali metal ions improving thermal stability is explained reasonably through the photoionization and trap compensation. This new strategy makes it possible for (Sr, Ba)2SiO4: Eu2+ phosphors to be wider applicated in the high-performance WLED devices. © 2022, The Authors. All rights reserved.