Luminescent Properties and Charge Compensator Effects of SrMo0.5W0.5O4:Eu3+ for White Light LEDs

• Published in: Molecules (Basel, Switzerland) Vol. 28; no. 6; p. 2681
• Main Authors: Kong, Li, Sun, Hao, Nie, Yuhao, Yan, Yue, Wang, Runze, Ding, Qin, Zhang, Shuang, Yu, Haihui, Luan, Guoyan
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 16.03.2023; MDPI
• Subjects: charge compensator; Doping; Emission spectra; Europium; Excitation spectra; Fluorescence; High temperature; Light emitting diodes; Luminescence; Luminescence performance; Phosphors; Solid phases; Solid solutions; Spectral emissivity; SrMo0.5W0.5O4:Eu3; Temperature; Ultraviolet radiation; w-LED; White light
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules28062681

The high-temperature solid-phase approach was used to synthesize Eu3+-doped SrMo0.5W0.5O4 phosphors, whose morphological structure and luminescence properties were then characterized by XRD, SEM, FT-IR, excitation spectra, emission spectra, and fluorescence decay curves. The results reveal that the best phosphor synthesis temperature was 900 °C and that the doping of Eu3+ and charge compensators (K+, Li+, Na+, NH4+) had no effect on the crystal phase change. SrMo0.5W0.5O4:Eu3+ has major excitation peaks at 273 nm, 397 nm, and 464 nm, and a main emission peak at 615 nm, making it a potential red fluorescent material to be used as a down converter in UV LEDs (273 nm and 397 nm) and blue light LEDs (464 nm) to achieve Red emission. The emission spectra of Sr1−yMo0.5W0.5O4:yEu3+(y = 0.005, 0.01, 0.02, 0.05, 0.07) excited at 273 were depicted, with the Eu3+ concentration increasing the luminescence intensity first increases and then decreases, the emission peak intensity of SrMo0.5W0.5O4:Eu3+ achieves its maximum when the doping concentration of Eu3+ is 1%, and the critical transfer distance is calculated as 25.57 Å. When various charge compensators such as K+, Li+, Na+, and NH4+ are added to SrMo0.5W0.5O4:Eu3+, the NH4+ shows the best effect with the optimal doping concentration of 3wt%. The SrMo0.5W0.5O4:Eu3+,NH4+ color coordinate is (0.656,0.343), which is close to that of the ideal red light (0.670,0.333).