Synthesis and photoluminescent properties of Sm3+-activated La3Si6N11 as an orange-red emitting phosphor

A series of Sm3+-doped La3Si6N11 phosphor materials were synthesized by a high temperature solid-state reaction method. The crystal structure, microstructure, photoluminescence properties, decay curves as well as thermal quenching properties of the as-prepared phosphors were investigated systematically. The excitation spectra contain a wide asymmetric band below 350 nm originating from the host absorption, several sharp excitation peaks in the range of 300-550 nm corresponding to f-f transition of Sm3+. Under the excitation of 369 and 414 nm light, the phosphors exhibit strong narrow-band orange-red emission peaked at 605 nm. The average decay time of La2.99Si6N11:0.01Sm(3+) sample is fitted to be 0.38 ms and the CIE coordinates were calculated to be (0.6105, 0.3833). For water resistance, La3Si6N11:Sm3+ is better than K2SiF6:Mn4+ phosphor. After soaking in deionized water for 300 min, the La3Si6N11:Sm3+ sample retains approximately 80% of its initial relative emission intensity. When the temperature rises to 423 K (150 degrees C), the emission intensity of La2.99Si6N11:0.01Sm(3+) sample remains 85% in comparison to that of room temperature. The activation energy was calculated to be 0.63253 eV, which is higher than those of Sm3+-activated oxide phosphors, indicating that the phosphor has relatively good thermal stability. (c) 2020 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.

Automated summary

In this study, Sm3+-doped La3Si6N11 phosphor materials were synthesized and characterized for their photoluminescence properties and thermal stability. The results indicated that the phosphors exhibited good optical performance and thermal stability.