Nature of Self-Trapped Exciton Emission in Zero-Dimensional Cs2ZrCl6 Perovskite Nanocrystals

Yanmei He; Siping Liu; Zehan Yao; Qian Zhao; Pavel Chabera; Kaibo Zheng; Bin Yang; Tönu Pullerits; Junsheng Chen

doi:10.1021/acs.jpclett.3c01878

Nature of Self-Trapped Exciton Emission in Zero-Dimensional Cs₂ZrCl₆ Perovskite Nanocrystals

J Phys Chem Lett. 2023 Aug 31;14(34):7665-7671. doi: 10.1021/acs.jpclett.3c01878. Epub 2023 Aug 21.

Authors

Yanmei He^{1

2}, Siping Liu^{3

4}, Zehan Yao¹, Qian Zhao⁵, Pavel Chabera¹, Kaibo Zheng^{1

5}, Bin Yang³, Tönu Pullerits¹, Junsheng Chen^{1

2}

Affiliations

¹ Department of Chemical Physics and NanoLund, Lund University, P.O. Box 124, 22100 Lund, Sweden.
² Nano-Science Center & Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.
³ State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 116023 Dalian, P. R. China.
⁴ Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530006, P. R. China.
⁵ Department of Chemistry, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.

Abstract

Low dimensional perovskite-inspired materials with self-tapped exciton (STE) emission have stimulated a surge of cutting-edge research in optoelectronics. Despite numerous efforts on developing versatile low-dimensional perovskite-inspired materials with efficient STE emissions, there is little emphasis on the intrinsic dynamics of STE-based broad emission in these materials. Here, we investigated the excited state dynamics in zero-dimensional (0D) Cs₂ZrCl₆ nanocrystals (NCs) with efficient blue STE emission. By using femtosecond transient absorption (fs-TA) spectroscopy, the ultrafast STE formation process within 400 fs is directly observed. Then, the formed STEs relax to an intermediate STE state with a lifetime of ∼180 ps before reaching the emissive STE state with a lifetime of ∼15 μs. Our work offers a comprehensive and precise dynamic picture of STE emission in low-dimensional metal halides and sheds light on extending their potential applications.