Double perovskite Ca2GdNbO6:Mn4+ deep red phosphor: Potential application for warm W-LEDs

• Published in: Superlattices and microstructures 2018-05, Vol.117, p.476-487
• Main Authors: Lu, Zuizhi, Huang, Tianjiao, Deng, Ruopeng, Wang, Huan, Wen, Lingling, Huang, Meixin, Zhou, Liya, Yao, Chunying
• Format: Article
• Language: English
• Subjects: Deep red-emitting; Mn4+-doped; Phosphors; Thermal stability
• ISSN: 0749-6036; 1096-3677
• DOI: 10.1016/j.spmi.2018.03.054

A novel Mn4+-doped Ca2GdNbO6 (CGN) phosphor was prepared by high-temperature solid-state reaction. The crystal structure was investigated by X-ray diffraction patterns and unit cell structure. Mn4+ replaced the location of Nb5+ in the CGN lattice, and the value of energy gap (Egap) decreased from 2.16 eV to 1.13 eV, indicating that Mn4+ ions play a great influence on the absorption of CGN hosts. The broad excitation band from 250 nm to 550 nm matches well with commercial near-UV light emitting diodes, and the emission peak centered at 680 nm is due to 2E→4A2g transition in Mn4+ ions. The CIE chromaticity coordinates (0.698, 0.303) of CGN:Mn4+ phosphor was close to standard red color coordinates (0.666, 0.333). These investigations demonstrate CGN:Mn4+ phosphor as an efficient red phosphor for potential applications. [Display omitted] •Red phosphors Ca2GdNbO6:Mn4+ phosphors were synthesized for the first time.•Board excitation bands can be efficiently excited by near-UV light to emit deep red emission.•Tanabe−Sugano energy level diagram is used to analysis the luminescence mechanism.•Temperature dependence spectra is investigated to demonstrate its good thermal stability.