Synthesis, structure and photoluminescence properties of a novel Rb2NaAlF6:Mn4+ red phosphor for solid-state lighting

• Published in: Journal of luminescence 2020-10, Vol.226, p.117491, Article 117491
• Main Authors: Shi, Dongxin, Liang, Zibo, Zhang, Xi, Zhou, Qiang, Wang, Zhengliang, Wu, Mingmei, Ye, Yanqing
• Format: Article
• Language: English
• Subjects: Luminescence properties; Rb2NaAlF6:Mn4; Red phosphor; White light-emitting diode
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2020.117491

In this work, we present a novel Mn4+-activated Rb2NaAlF6 red phosphor synthesized through a cation exchange route at room temperature. The structural and optical features were characterized by X-ray diffraction, energy dispersive X-ray spectrometer, scanning electron microscopy, X-ray fluorescence, emission, excitation, and luminescence decay curves. The straightforward evidences have shown that the as-prepared Rb2NaAlF6:Mn4+ crystallizes into single cubic phase with regular octahedral particulate morphology, and exhibits broad excitation band and sharp emission lines in the red and blue regions. The luminescence properties, thermal stability and optical performance were systematically investigated to recognize the luminescence behavior of Rb2NaAlF6:Mn4+ and its potential application for white light illumination. The results suggest that the Rb2NaAlF6:Mn4+ phosphor exhibits excellent thermal stability and is capable of tuning the cold white light to warm in white light-emitting diodes. A novel fluoroaluminate red-emitting phosphor of Rb2NaAlF6:Mn4+, showing regular octahedral particulate morphology, outstanding thermal stability, intense red emission lines and broad blue excitation band characteristics, was presented in this work. With the introduction of this phosphor, the Ra and Tc data of commercial WLED can be significantly improved, indicating its potential use for warm white light illumination. [Display omitted] •The red luminescence from a novel Rb2NaAlF6:Mn4+ red phosphor was presented.•The crystal structure and luminescence properties have been confirmed.•The concentration quenching mechanism and optical performance have been elucidated.