A novel Mn4+ doped oxyfluoride red phosphor for rapid-response backlights display. Issue 32 (6th August 2020)

• Record Type: Journal Article
• Authors: He, Shengan; Yao, Liqin; Cai, Wenting; Wu, Di; Peng, Jiaqing; Ye, Xinyu
• Is Part Of: Dalton transactions. Volume 49:Issue 32(2020)
• Page Start: 11290
• Page End: 11299
• Publication Date: 2020-08-06
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0dt02093a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : An oxyfluoride red phosphor Cs2 MoO2 F4 :Mn 4+ was synthesized with a short fluorescence lifetime, and can be applied to rapid-response displays. Abstract : An oxyfluoride red phosphor Cs2 MoO2 F4 :Mn 4+ was synthesized via a facile co-precipitation route with a certain molecular ratio of CsF and MoO3 . X-ray diffraction analysis and its Rietveld refinement reveal that Cs2 MoO2 F4 :Mn 4+ crystallized in an orthorhombic structure with the Amam (63) space group. Upon blue light excitation, Cs2 MoO2 F4 :Mn 4+ exhibits a series of sharp red emission lines around ∼634 nm and the zero-phonon line (ZPL) is visible at 619 nm. The optimal doping amount of Mn 4+ in Cs2 MoO2 F4 is 1.12%, and the decay curves show a good fit with the single exponential decay model. The fluorescence lifetime of the synthesized phosphors is relatively short and calculated as 3.18 to 2.46 ms, the Mn 4+ ions in Cs2 MoO2 F4 experience a strong crystal field strength with a Dq / B of ∼4.87, and the distinct nephelauxetic ratio β 1 is determined to be ∼1.0226. The thermal quenching mechanism of Mn 4+ was also studied. Furthermore, by using the as-synthesized Cs2 MoO2 F4 :Mn 4+ phosphor as a red component and β-SiALON as a green light component, a WLED was fabricated with a high luminous efficacy of 114.70 lm·W −1 and wide color gamut of 109.1% of the National Television Standard Committee (NTSC) value. Hence, the Cs2 MoO2 F4 :Mn 4+ phosphor with a short fluorescence lifetime could potentially be an efficient red compensator for application in rapid-response backlight displays.