Designing a Polyphosphate Polymorph of CsMg(PO₃)₃ as Host Lattice for Preparing Single Mn²⁺-Oxidation Doped Phosphor in the Open Environment

Abstract

Within Mn-activated phosphors, the oxidation state of Mn dopant strongly depends on the structural features of the host lattice. This paper reported a new polymorph of CsMg(PO 3 ) 3 (CMP) with a complicated three-dimensional (3D) framework of [Mg(PO 3 ) 3 ] ∞ that is constructed by MgO 6 octahedra and 1D infinite [PO 3 ] ∞ chains. Then we prepared a series of red phosphors CsMg 1−x (PO 3 ) 3 :xMn 2+ (CMP:xMn 2+ ) by high temperature solid state reactions in the open air. Powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) studies revealed the single Mn 2+ -oxidation. Under 404 nm light exciting, CMP:0.2Mn 2+ can emit single-band emission at around 630 nm with full-width at half-maximum (fwhm) of 70 nm. Besides, CMP:0.2Mn 2+ possesses excellent thermostability up to 450 K. These features indicate that CMP:0.2Mn 2+ is suitable to be used for LED backlight display. Moreover, this work suggests that a host lattice with suitable structure feature can form single Mn 2+ -oxidation and is rigid enough to protect Mn 2+ from being oxidized by O 2 at high temperature.

Achieving highly thermostable red emission in singly Mn2+-doped BaXP2O7 (X = Mg/Zn) via self-reduction

“…4, two sets of broad bands correspond to Mn 2p 3/2 and 2p 1/2 orbitals. Attention is primarily paid to the satellite peaks of Mn 2+ ranging from 645 to 649 eV, 36,37 which is found in MnCO 3 but not in MnO 2 . Obviously, the satellite peaks of Mn 2+ appear in both BMPO:Mn 2+ and BZPO:Mn 2+ , specifying the presence of Mn 2+ in the phosphors.…”

“…[18][19][20] However, the Mn 2+doped phosphors often show poor heat resistance. 21,22 A rigid structural framework usually increases the thermal quenching (TQ) temperature because of reduced electron-phonon coupling. [23][24][25] Another promising way is to generate proper charge defects to compensate for TQ nonradiative loss to improve the thermal stability of phosphors.…”

Broad luminescence tuning in Mn2+-doped Rb2Zn3(P2O7)2via doping level control based on multiple synergies

“…The PL intensities of all the samples decreased with increasing ambient temperature due to nonradiative transitions under a high working temperature. 29 The PL spectra of the RZPO: x Mn 2+ samples at 200 °C show blue shift compared with that at 25 °C, which may be caused by a thermally active phonon-assisted tunneling process 30 and a decreased crystal field at high temperatures caused by the lattice expansion. 31 Fig.…”

X-ray-Irradiation-Induced Discoloration and Persistent Radioluminescence for Reversible Dual-Mode Imaging and Detection Applications

“…The XPS spectra of the manganese element in the BMS:Mn phosphor was measured (Figure a). The resulting spectra exhibited two broad peaks located at 640.54 eV and 652.36 eV, which correspond well with the Mn 2 p 3/2 and Mn 2 p 1/2 signals of Mn 2+ ions . Compared to the XPS spectra of the Mn element from the original BMS:Mn phosphor, the valence state of the Mn element did not change after X-ray (photochromism) and 254 nm light (decoloration) irradiation (Figure a).…”