A zinc non-halide dopant strategy enables efficient perovskite CsPbI3 quantum dot-based light-emitting diodes. (16th March 2020)

• Record Type: Journal Article
• Authors: Li, Jinhang; Chen, Jiawei; Xu, Leimeng; Liu, Sinan; Lan, Si; Li, Xiansheng; Song, Jizhong
• Is Part Of: Materials chemistry frontiers. Volume 4:Number 5(2020)
• Page Start: 1444
• Page End: 1453
• Publication Date: 2020-03-16
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/c9qm00734b
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : A zinc non-halide dopant strategy is employed to clarify the internal mechanism of Zn 2+ doping without the introduction of halide ions and enhance the emission properties evidenced by the EQE of the QLEDs from 7.5% to 14.6% after Zn 2+ doping. Abstract : Metal ion doping has been considered as one of the most effective methods to achieve highly efficient perovskite light-emitting diodes (LEDs), which is significant for future high-definition displays and high-quality lighting. However, its exact function is still uncertain because the doping of metal ions is also accompanied by the introduction of halide ions and halide-rich circumstances, which can enhance the optoelectronic properties as well. In this work, a zinc non-halide dopant strategy was employed to specifically study the effect of Zn 2+ on CsPbI3 quantum dots (QDs). We confirmed that Zn 2+ was doped into the perovskites interstitially via X-ray diffraction (XRD) and pair distribution function (PDF) analysis. Zn 2+ -doped CsPbI3 QDs exhibited higher emission properties with 120% enhancement in the photoluminescence quantum yield (PLQY) compared with pristine CsPbI3 QDs. The Zn 2+ -doped CsPbI3 QD-based LEDs (QLEDs) showed nearly two-fold increase in the external quantum efficiency (EQE) versus the control device, and it improved from 7.5% to 14.6%. Besides, a maximum current efficiency of 0.83 cd A −1 and the highest luminance of 378 cd m −2 were achieved. These results certify that Zn 2+ doping enables high-performance QLEDs without the introduction of halide ions, which is beneficial for the further research on doped perovskite fields and lays the foundation for the future practical applications of QLEDs.