Thermally robust and valence-variation-induced white-light emission of a novel stannate phosphor Sr3Al10SnO20:Dy3+: crystal structure, luminescence property, and mechanism investigation. Issue 44 (5th November 2020)

• Record Type: Journal Article
• Authors: Xin, Shuangyu; Gao, Miao; Ma, Jialing; Dai, Heng; Zhu, Ge
• Is Part Of: Dalton transactions. Volume 49:Issue 44(2020)
• Page Start: 15800
• Page End: 15809
• Publication Date: 2020-11-05
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0dt02899a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Structure, luminescence property, and mechanism investigation of a valence-variation-induced tunable white-light emission of a novel stannate phosphor with robust thermal stability. Abstract : The development of novel white-light-emission phosphors is of great importance for applications in lighting and display fields. Trivalent Dy 3+ is widely used as a potential luminescence center for white-light emission. However, Dy 3+ -doped phosphors often suffer a poor yellow to blue ratio due to the deficiency of its 4 F9/2 → 6 H15/2 transition, low luminescence efficiency, and unsatisfactory thermal stability. The importance of the present research work is that we have achieved a tunable white light in a single phased stannate phosphor Sr3 Al10 SnO20 :Dy 3+ with robust thermal stability. The crystal structure, phase purity, and chemical composition were investigated via X-ray diffraction Rietveld structure refinement, scanning electron microscopy, and energy dispersive spectrometry. The luminescence spectra indicated that Sr3 Al10 SnO20 :Dy 3+ not only exhibited characteristic 4 F9/2 → 6 H J /2 ( J =11, 13, and 15) inherent transition emissions of Dy 3+, but also showed an abnormal blue band emission, which was identified through X-ray photoelectric spectroscopy as the T1 → S0 transitions of Sn 2+, resulting from the valence variation of Sn 4+ . The efficient energy transfer from Sn 2+ to Dy 3+ was also confirmed and the transfer efficiency was calculated. Owing to the valence-variation-induced emission of Sn 2+, a tunable white light could be realized from a cool to warm white light region, with Commission Internationale de l'Eclairage coordinates and a correlative color temperature varying from (0.277, 0.333) and 8634 K to (0.353, 0.404) and 4913 K, respectively. The luminescent and defects formation mechanism as well as the luminescence kinetics were further investigated. Moreover, Sr3 Al10 SnO20 :Dy 3+ had a high quantum efficiency (∼34.6%) and a super-stable thermal stability behavior (82.5% at 240 °C of the initial integral emission intensity at 30 °C) with a large activation energy (Δ E ∼ 0.1654 eV). Finally, a charge-compensation test was performed to further verify the effect of defects on the luminescence property and the related mechanism was discussed. The current work provides a novel method to achieve tunable white-light emission in Dy 3+ single-doped phosphors and the related mechanism is effectual for other rare earths for potential applications in lighting and display fields.