Mn4+-doped La(CaZr)0.5O3 phosphors for plant grow LEDs: Ab initio site occupy and photoluminescence properties. (March 2022)

• Record Type: Journal Article
• Authors: Meng, Yingbin; Chen, Peican; Fan, Hua; Lu, Zuizhi; Zhong, Xiaoying; Lu, Jiangying; Ou, Yingjun; Zhou, Liya
• Is Part Of: Materials research bulletin. Volume 147(2022)
• Publication Date: 2022-03
• Subjects: Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2021.111610
• Languages: English
• ISSNs: 0025-5408

Abstract

Highlight: La(CaZr)0.5 O3 : Mn 4+ phosphors were prepared successfully by traditional solid-state reaction method. We discuss the possible site of Mn 4+ ions by formation energy, bond length, density of state, valence charge density, and Bader charge based on density functional theory. The PL spectra of La(CaZr)0.5 O3 : Mn 4+ phosphors could match with the absorption spectra of PFR and PR . Abstract: The La(CaZr)0.5 O3 : Mn 4+ (LCZ: Mn 4+ ) phosphors are synthesized by the conventional solid-state method. The crystal structure, surface morphology, optical properties, and thermal properties of LCZ are investigated in detail. So far, the site where Mn 4+ might occupy in the host is rarely discussed. Herein, we discuss the possible site of Mn 4+ ions by formation energy, bond length, density of state, valence charge density, and Bader charge based on density functional theory. Compared with the host, the doped phosphor has a stronger light absorption capacity and a wider light absorption range. The doped phosphors can emit deep-red light that centered at 694 nm under the n-UV (347 nm) and blue light (530 nm) excitation at room temperature. The critical quenching concentration of Mn 4+ is 0.006, and the mechanism of concentration quenching is the dipole–dipole interaction between Mn 4+ ions. The photoluminescence intensity of 100 °C remains at 16.5% of the initial intensity at room temperature. What's more, the emission band of phosphors overlaps with absorption spectra of plant, indicating its potential application value in plant growing light-emitting diodes. Graphical abstract: We investigate the occupied site of the Mn 4+ ions in LaCa0.5 Zr0.5 O3 base on the density functional theory. Image, graphical abstract