One-step low-temperature solid-state synthesis of lead-free cesium copper halide Cs3Cu2Br5 phosphors with bright blue emissions. (March 2022)

• Record Type: Journal Article
• Authors: Huang, Xiaoyong; Wang, Shaoying; Devakumar, Balaji; Ma, Nan
• Is Part Of: Materials today chemistry. Volume 23(2022)
• Publication Date: 2022-03
• Subjects: Quantum yield -- Luminescence -- Solid-state reaction -- Stability; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2021.100678
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: The development of new efficient and environmental-friendly inorganic phosphors is highly important for phosphor-converted white light-emitting diodes and optoelectronic displays. In this paper, we report a novel and simple one-step solid-state reaction to synthesize lead-free cesium copper halide Cs3 Cu2 Br5 powders with bright blue emission around 460 nm. The preparation process is performed at low calcination temperatures (290–320 °C) and requires no complex apparatus, reagents, or techniques, and thus it holds great potential for mass production of halide emitters. The Cs3 Cu2 Br5 powder phosphors are characterized by X-ray diffraction, field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, photoluminescence excitation and emission spectroscopy, CIE color coordinates, color purity, photoluminescence quantum yield, and temperature-dependent emission spectra. The effect of calcination temperature on the photoluminescence properties of the as-prepared Cs3 Cu2 Br5 blue phosphors has been investigated and the air-stability property has also been discussed. Impressively, Cs3 Cu2 Br5 blue phosphors show outstanding stability toward air exposure exceeding one month (30 days). Our work will open a new and simple approach to obtain excellent halide emitters for future solid-state lighting and displays. Graphical abstract: A novel and simple one-step low-temperature solid-state reaction method is proposed to prepare lead-free cesium copper halide Cs3 Cu2 Br5 blue-emitting phosphors. Image 1 Highlights: Blue-emitting Cs3 Cu2 Br5 phosphors were prepared by a solid-state method. They produced intense broadband blue emissions around 460 nm. Effects of calcination temperature on the PL properties were studied. PLQY was determined to be 23%. Thermal and air stabilities were investigated.