A novel efficient broadband near-infrared phosphor LiGaGe2O6:Cr3+ with EQE enhancement and spectral tuning by Sc3+–Ga3+ substitution for NIR pc-LED application. Issue 2 (30th November 2022)

• Record Type: Journal Article
• Authors: Fan, Jiaqi; Zhou, Weiying; Zhang, Jilin; Chen, Peichan; Pang, Qi; Zhou, Liya; Zhou, Chunyan; Zhang, Xinguo
• Is Part Of: Inorganic chemistry frontiers. Volume 10:Issue 2(2023)
• Page Start: 511
• Page End: 521
• Publication Date: 2022-11-30
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2qi02054h
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : High-efficint LiGaGe2 O6 :Cr 3+ NIR phosphor is explored, and the quantum efficiency could be boosted by Sc-Ga substitution. Abstract : Most of the NIR emitting materials reported until now are limited by their low external quantum efficiency. Developing highly efficient and tunable broadband near-infrared phosphors remains a significant challenge for realizing their multi-applications. Herein, a gallate, LiGaGe2 O6, was selected as the host for Cr 3+ doping, while its crystal and electronic structures were revealed using the Rietveld refinement and DFT calculations. On irradiating this LiGaGe2 O6 :Cr 3+ phosphor with 460 nm blue light, it generates a broadband NIR emission ( λ em = 830 nm) covering the 700–1200 nm region with a full width at half maximum of 192 nm. A promising external quantum efficiency (EQE) of 27.9% could be achieved at an optimal Cr 3+ content of 0.06. It was found that a spectral tuning with the peak position in the range of 830–890 nm was realized by the Sc 3+ –Ga 3+ substitution with a decreasing crystal field strength. Meanwhile, the optimized Li(Ga0.24 Sc0.70 )Ge2 O6 :Cr 3+ exhibited an enhanced EQE of 47.8%. The variation of emission thermal stability by Sc 3+ substitution was investigated. The prepared phosphor-converted light-emitting diode (pc-LED) device generated an intense NIR emission (25.3 mW at 100 mA) with a photoelectric efficiency of 10%. Thus, this work not only provides a novel high-performance broadband NIR phosphor for NIR pc-LED, but also demonstrates that cationic substitution is an effective strategy to tune and enhance the NIR optical properties of Cr 3+ -doped phosphors.