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  • Simultaneous Synthesis, Modification, and DFT Calculation of Three‐Color Lead Halide Perovskite Phosphors for Improving Stability and Luminous Efficiency of WLEDs
Title: Simultaneous Synthesis, Modification, and DFT Calculation of Three‐Color Lead Halide Perovskite Phosphors for Improving Stability and Luminous Efficiency of WLEDs
Abstract The all‐inorganic metal halide perovskite CsPbX3(X = Cl, Br, and I) has received extensive attention in the field of white light‐emitting diodes (WLEDs) due to its high luminous intensity and high color purity. However, the shortcoming of poor stability directly affects the luminous performance of the WLED devices and reduces their luminous efficiency, which has become an urgent problem to be solved. Here, three‐color lead halide perovskite phosphors (blue‐emitting CsPbBr3synthesized at 20 °C (CPB‐20), green‐emitting CsPbBr3‐80 (CPB‐80)/CsPbBr3:SCN−(CPB:SCN−), and red‐emitting PEA2PbBr4(PPB)/PEA2PbBr4:Mn2+(PPB:Mn2+)) with higher stability and luminous intensity are simultaneously prepared and applied in WLEDs. Density functional theory is used to optimize the structures of CsPbBr3and PEA2PbBr4, and to calculate the work function, optical properties, and charge density difference. Not only the WLED devices with three‐color lead halide perovskite phosphors are constructed, but also WLED devices from warm white to cold white are realized by tuning the ratio of the different emissions, and a superior color quality (color rendering index of 96) and ideal correlated color temperature (CCT of 9376 K) are achieved. This work will set the stage for exploring low‐cost, environmentally friendly, high‐performance WLEDs.  more » « less
Award ID(s):
1945558
PAR ID:
10362289
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Optical Materials
Volume:
10
Issue:
2
ISSN:
2195-1071
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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