Local structure engineering of Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2+ green phosphors for violet-light-excitable full-spectrum lighting

• Published in: Journal of alloys and compounds 2024-12, Vol.1007, Article 176407
• Main Authors: Zhu, Shuangyin, Jin, Shilin, Pang, Tao, Zeng, Lingwei, Lei, Lei, You, Fengluan, Fang, Yongzheng, Chen, Daqin
• Format: Article
• Language: English
• Subjects: Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2; Full-spectrum lighting; Green phosphors; Structure engineering
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.176407

To achieve comfortable and healthy full-spectrum lighting, the development of efficient and stable violet-light-excitable phosphors is urgently required. Herein, we report a new type of green-emitting phosphor, Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2+ (x=0–1). Interestingly, K+-alloying leads to continuous redshift of green emission from 500 nm to 517 nm accompanied with reduced full width at half maximum (FWHM) from 72 nm to 63 nm and enhanced excitation intensity in the violet spectral region. Rietveld refinements and spectral analysis evidence that K+-addition enhances the distortion of [M(Ⅰ)O9] and [M(Ⅱ)O7] (M(Ⅰ/Ⅱ) = Ba, La, Y, K) polyhedron and strengthens crystal field around Eu2+, which is responsible for the observed photoluminescence (PL) phenomenon. Finally, we design a full-spectrum white light emitting diode (WLED) with an ultra-high color rendering index (CRI, Ra) of 97.4 by coupling the as-prepared green-emitting phosphor (Ba0.7K0.3La2Y2(SiO4)2O1-α: Eu2+) and commercial blue/red phosphors with a violet LED chip, which demonstrates significant potential for application in healthy solid-state lighting. [Display omitted] •A K+ alloyed Ba1-xKxLa2Y2(SiO4)2O1-α: Eu2+ phosphor has been developed.•The sample meets the requirements of commercial violet chip excitation LED.•The introduction of K+ ions improves the luminescence performance and thermal stability.•The full spectrum LED shows excellent performance.