Synergistic ligand mediated anion exchange of CsPbI3 quantum dots for high performance white LED and anti‐counterfeiting
Yajing Chang,
Guoqing Tong,
Liping Liu,
Junchun Li,
Jingting Yang,
Zongsheng Chen,
Zhigang Li,
Shaobo Zhang,
Ru Zhou,
Yang Jiang
Affiliations
Yajing Chang
State Key Laboratory of Pulsed Power Laser Technology/Advanced Laser Technology Laboratory of Anhui Province National University of Defense Technology Hefei People's Republic of China
Guoqing Tong
School of Materials Science and Engineering Hefei University of Technology Hefei People's Republic of China
Liping Liu
State Key Laboratory of Pulsed Power Laser Technology/Advanced Laser Technology Laboratory of Anhui Province National University of Defense Technology Hefei People's Republic of China
Junchun Li
School of Materials Science and Engineering Hefei University of Technology Hefei People's Republic of China
Jingting Yang
School of Materials Science and Engineering Hefei University of Technology Hefei People's Republic of China
Zongsheng Chen
State Key Laboratory of Pulsed Power Laser Technology/Advanced Laser Technology Laboratory of Anhui Province National University of Defense Technology Hefei People's Republic of China
Zhigang Li
State Key Laboratory of Pulsed Power Laser Technology/Advanced Laser Technology Laboratory of Anhui Province National University of Defense Technology Hefei People's Republic of China
Shaobo Zhang
College of Physical Science and Technology/Microelectronics Industry Research Institute Yangzhou University Yangzhou People's Republic of China
Ru Zhou
School of Electrical Engineering and Automation Hefei University of Technology Hefei People's Republic of China
Yang Jiang
School of Materials Science and Engineering Hefei University of Technology Hefei People's Republic of China
Abstract Anion exchange is an effective strategy to regulate the composition and optoelectronic properties of perovskite quantum dots (PQDs). Though promising, it is more desirable to synthesize PQDs to avoid the decrease of photoluminescence quantum yield (PLQY). Herein, we developed a ligand mediated anion exchange approach, in which the phase transition from CsPbBr3 QDs to CsPbI3 QDs was observed with the introduction of N‐Acetyl‐l‐cysteine (NAC) and 1,3‐dimethylimidazolium iodide (DMII) aqueous solution in CsPbBr3 QDs solution. NAC is expected to create more halogen vacancies in CsPbBr3 QDs, which provides sufficient adsorption sites for I− ions, resulting in accelerating the anion exchange rate in the process of DMII incorporation. Benefiting from the synergistic ligand mediated anion exchange, high PLQY of 97% and remarkable stability of CsPbI3 QDs are obtained. Furthermore, a white light‐emitting diode (WLED) with a lumen efficiency (LE) of 116.82 lm/W is constructed, showing remarkable stability under continuous operation.
