Crystal-field induced tuning of luminescence properties of Na3GaxAl1−xF6:Cr3+ phosphors with good thermal stability for NIR LEDs. Issue 29 (1st July 2022)

• Record Type: Journal Article
• Authors: Zhou, Jianbang; Chen, Pengyun; Li, Junhao; Yang, Mingming; Jiang, Wei; Zhang, Qiuhong; Ni, Haiyong; Huo, Jiansheng
• Is Part Of: Dalton transactions. Volume 51:Issue 29(2022)
• Page Start: 10965
• Page End: 10972
• Publication Date: 2022-07-01
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt01559e
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The crystal field, PL intensity, peak position and FWHM of Cr 3+ -activated Na3 Ga x Al1− x F6 :Cr 3+ phosphors can be well controlled by changing the Ga/Al ratio. Abstract : Cr 3+ -Activated broadband near-infrared (NIR) luminescence materials are attracting much attention as next-generation smart NIR light sources that are widely used in night vision, bioimaging, medical treatment, and many other fields. Herein, a series of Na3 Ga x Al1− x F6 :Cr 3+ NIR phosphors with broadband emission and tunable luminescence properties were designed and prepared. The luminescence intensity, peak position and full width at half maximum (FWHM) of the materials can be controlled by adjusting the crystal field strength. Furthermore, Na3 Ga0.75 Al0.25 F6 :0.35Cr 3+ exhibited high luminous efficiency and the emission intensity remained 81% at 423 K compared with the initial value at 298 K. The structural confinement and the electron–phonon coupling (EPC) effect may account for its good thermal stability. Finally, a pc-NIR-LED device with a photoelectric conversion efficiency of 6.53% at 350 mA was fabricated by combining the as-prepared NIR phosphor and a blue InGaN chip, and its applications in night vision and medical fields were further investigated. This work will promote the development of NIR phosphors with tunable luminescence properties.