Perovskite Quantum Dots with Ultrahigh Solid-State Photoluminescence Quantum Efficiency, Superior Stability, and Uncompromised Electrical Conductivity

Jun Bo; Xiaojuan Sun; Peng Wan; Dong Huang; Xingtong Chen; Mengyu Chen; Rui Li; Dongyang Shen; Qinyi Li; Wenlin Xia; Zi Ye; Yu Chen; Song Chen

doi:10.1021/acs.jpclett.1c02472

Perovskite Quantum Dots with Ultrahigh Solid-State Photoluminescence Quantum Efficiency, Superior Stability, and Uncompromised Electrical Conductivity

J Phys Chem Lett. 2021 Sep 23;12(37):9115-9123. doi: 10.1021/acs.jpclett.1c02472. Epub 2021 Sep 16.

Authors

Jun Bo¹, Xiaojuan Sun¹, Peng Wan¹, Dong Huang², Xingtong Chen¹, Mengyu Chen¹, Rui Li¹, Dongyang Shen², Qinyi Li², Wenlin Xia², Zi Ye¹, Yu Chen², Song Chen¹

Affiliations

¹ College of Chemistry, Chemical Engineering and Materials Science,Soochow University, Suzhou, Jiangsu215123, China.
² School of Optical Science and Engineering, Soochow University, Suzhou, Jiangsu215006, China.

PMID: 34528436
DOI: 10.1021/acs.jpclett.1c02472

Abstract

All-inorganic perovskite quantum dots (PQDs), potentially applicable to high-performance display technologies, are facing challenges when the superior luminescence properties with high stability and uncompromised electrical conductivity are combined. Here, by introducing hexylamine sulfate and reducing the reaction rate, we managed to optimize the surface sacrificial coating of CsPbBr₃ QDs. As a result, the colloidal PQDs show a photoluminescence quantum efficiency (PLQE) of 95.8% in solution, and an internal PLQE as high as 97.8% in solid-state films. As far as stability is concerned, the PQDs not only show excellent resistance to polar solvent but also can retain over 84% of the initial PL intensity after continuous heating at 100 °C for 60 min. More importantly, the superior stability is achieved without compromising electrical conductivity. The light-emitting diodes made from these PQDs show a current efficiency of 8.9 cd A^-1 with excellent thermal stability.