High-efficient, spherical and thermal-stable carbon dots@silica fluorescent composite as rare earth-free phosphors for white LED. Issue 10 (July 2020)

• Record Type: Journal Article
• Authors: Zhang, Xinguo; Sun, Zishan; Zhu, Zhenpng; Luo, Jiabao; Wu, Zhanchao; Wang, Zhengliang
• Is Part Of: Ceramics international. Volume 46:Issue 10(2020)Part A
• Page Start: 14706
• Page End: 14712
• Publication Date: 2020-07
• Subjects: Composite phosphors -- Carbon dots -- Silica nano-sphere -- Luminescence -- Light-emitting diodes; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2020.02.274
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: This paper reported a facile synthesis path to realize high-luminescent rare-earth-free composite powder, by embedding blue/green-emitting N-doped carbon dots into silica nano-spheres (CD@SiO2 ). Carbon dots were evenly dispersed in CD@SiO2 composites and eventually the aggregation-induced luminescence quenching is eliminated. Compared to the naked CDs, CD@SiO2 composites exhibit perfectly spherical morphology with average size of ~200 nm, significantly enhanced emission intensity (>4 times) and better thermal stability ( T 50 > 150 °C). As-synthesized CD@SiO2 own strong blue/green emission with high quantum efficiency (QE) over 60%. White LEDs prototypes with promising properties, i.e. CRI = 89.1, CCT = 4850 K and CIE coordinates = (0.3514, 0.3715), were fabricated by combining blue/green CD@SiO2 and red CdTe@CaCO3 composites with NUV chip. All results indicate that these rare-earth-free, mono-dispersed spherical, and thermal-stable composite materials with efficient blue/green emission could be an exceptional choice as phosphors for LED application.