Achieving highly thermostable red emission in singly Mn2+-doped BaXP2O7 (X = Mg/Zn) via self-reduction. Issue 13 (25th May 2022)

• Record Type: Journal Article
• Authors: Li, Song; Hu, Wei; Brik, Mikhail G.; Lian, Shixun; Qiu, Zhongxian
• Is Part Of: Inorganic chemistry frontiers. Volume 9:Issue 13(2022)
• Page Start: 3224
• Page End: 3232
• Publication Date: 2022-05-25
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2qi00539e
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : A self-reduction strategy realizes singly Mn 2+ -doped BaXP2 O7 (X = Mg/Zn) red phosphors with anti-thermal quenching performance, which have promising applications in warm WLED or plant growth lighting. Abstract : Non-rare earth doped red phosphors are attracting wide attention for warm-white lighting and indoor plant cultivation applications. Mn 2+ -doped phosphors have good spectral tunability and great potential to generate red emissions with comparable spectral profiles to commercial materials but with poor thermal resistance. Herein, two kinds of Mn 2+ -doped BaXP2 O7 (X = Mg/Zn) red-emitting phosphors are produced via self-reduction in air. The XPS, EPR, and optical spectroscopy measurements confirm the stabilization of manganese in the divalent state Mn 2+ . The BaMgP2 O7 :Mn 2+ (BMPO:Mn 2+ ) phosphor has an emission band at around 620 nm, matching well with the photopic spectral luminous efficiency curve. BaZnP2 O7 :Mn 2+ (BZPO:Mn 2+ ) exhibits a deep-red broad emission at about 670 nm, which overlaps with the chlorophyll and phytochrome absorption peaks. To realize the Mn 4+ → Mn 2+ self-reduction, intrinsic defects are generated, which serve as charge traps to compensate for the nonradiative loss at elevated temperatures. As a result, both phosphors exhibit anti-thermal quenching (anti-TQ) behaviors within 200 °C, and even at 250 °C, BMPO:Mn 2+ and BZPO:Mn 2+ retain 108% and 101% of the initial luminescence intensity at room temperature, respectively. Anti-TQ is rarely observed in singly Mn 2+ -doped phosphors. The self-reduction strategy in a rigid matrix lattice provides an effective way to improve the thermal stability of Mn 2+ -luminescence. The spectral compatibility and high thermal resistance of the pyrophosphate phosphors highlight their promising applications in warm-white LED or plant growth lighting.