Highly stable CsPbBr3 quantum dots coated with alkyl phosphate for white light-emitting diodes. Issue 40 (4th October 2017)

• Record Type: Journal Article
• Authors: Xuan, Tongtong; Yang, Xianfeng; Lou, Sunqi; Huang, Junjian; Liu, Yong; Yu, Jinbo; Li, Huili; Wong, Ka-Leung; Wang, Chengxin; Wang, Jing
• Is Part Of: Nanoscale. Volume 9:Issue 40(2017)
• Page Start: 15286
• Page End: 15290
• Publication Date: 2017-10-04
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7nr04179a
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : A simple strategy to synthesize TDPA coated CsPbBr3 QDs with improved stability and high PLQY. Abstract : Inorganic halide perovskite quantum dots (QDs) suffer from problems related to poor water stability and poor thermal stability. Here we developed a simple strategy to synthesize alkyl phosphate (TDPA) coated CsPbBr3 QDs by using 1-tetradecylphosphonic acid both as the ligand for the CsPbBr3 QDs and as the precursor for the formation of alkyl phosphate. These QDs not only retain a high photoluminescence quantum yield (PLQY, 68%) and narrow band emission (FHWM ∼ 22 nm) but also exhibit high stability against water and heat. The relative PL intensity of the QDs was maintained at 75% or 59% after being dispersed in water for 5 h or heated to 375 K (100 °C), respectively. Finally, white light-emitting diodes (WLEDs) with a high luminous efficiency of 63 lm W −1 and a wide color gamut (122% of NTSC) were fabricated by using green-emitting CsPbBr3 /TDPA QDs and red-emitting K2 SiF6 :Mn 4+ phosphors as color converters. The luminous efficiency of the WLEDs remained at 90% after working under a relative humidity (RH) of 60% for 15 h, thereby showing promise for use as backlight devices in LCDs.