Intense enhancement of yellow luminescent carbon dots coupled with gold nanoparticles toward white LED. (May 2017)

• Record Type: Journal Article
• Authors: Zhang, Yijun; Zhang, Jiaqi; Zhang, Junwen; Lin, Sai; Huang, Yunyun; Yuan, Rongrong; Liang, Xiaojuan; Xiang, Weidong
• Is Part Of: Dyes and pigments. Volume 140(2017)
• Page Start: 122
• Page End: 130
• Publication Date: 2017-05
• Subjects: Carbon nanodots -- Au nanoparticles -- GCDs film -- Fluorescence enhancement -- White LED; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2017.01.043
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: A novel gold-carbon dots (GCDs) exhibiting relatively high luminescence have been successfully synthesized by a facile solution cast method. Intriguingly, colloidal Au nanoparticles (Au NPs) present an enhancement effect on the photoluminescence of CDs, which can be attributed to the metal enhanced fluorescence (MEF) included two cooperative mechanisms and near-field interactions. Significantly, the 1.5–3 fold enhancement was obtained in the vicinity of Au NPs. The formation mechanism and chemical structure of the as-prepared GCDs were verified by a series of characterization techniques, such as high-resolution transmission electron microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The GCDs with optimal fluorescence was acquired by varying volume ratio of colloidal Au NPs to CDs, rendering bright visible light under 460 nm excitation and high quantum yield (QY) of 39%. Given that, a simple spin coating technology was developed for fabricating GCDs film composed of GCDs solution and quartz glass. Subsequently, GCDs-based white light emitting diodes (white LED) was designed through integrating blue LED chips with the yellow light-emitting GCDs film. In addition, the GCDs film at appropriate thickness possesses excellent optical performances with the corresponding optimized color coordinate (CIE) of (0.33, 0.36), the color rendering index (CRI) of 78.2, correlated color temperature (CCT) of 5653 K, and the luminous efficiency (LE) approaching to 43.75 lm W −1 . These superior results demonstrate that GCDs constitute a versatile and effective route for achieving high-performance white LED. Graphical abstract: Highlights: A novel gold-carbon dots (GCDs) have been successfully synthesized. The fluorescence of CDs was enhanced strongly by Au NPs. The mechanisms on the fluorescence enhancement of GCDs are given. The film consisted of GCDs and quartz glass was used in white LED.