Electronic structure and effective mass of pristine and Cl-doped CsPbBr₃

Journal Article · Wed May 01 00:00:00 EDT 2024 · Chinese Physics B

DOI:https://doi.org/10.1088/1674-1056/ad3c31· OSTI ID:2406825

Wei, Zhiyuan ^[1]; Wei, Yu-Hao ^[2]; Xu, Shendong ^[3]; Peng, Shuting ^[4]; Hashimoto, Makoto ^[5]; Lu, Donghui ^[5]; Pan, Xu ^[3]; Kuang, Min-Quan ^[2]; Xiao, Zhengguo ^[4]; He, Junfeng ^[4]

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1. Univ. of Science and Technology of China, Hefei (China); SLAC
2. Southwest University, Chongqing (China)
3. Chinese Academy of Sciences (CAS), Hefei (China). Hefei Institutes of Physical Science
4. Univ. of Science and Technology of China, Hefei (China)
5. SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)

Organic–inorganic lead halide perovskites (LHPs) have attracted great interest owing to their outstanding optoelectronic properties. Typically, the underlying electronic structure would determinate the physical properties of materials. But as for now, limited studies have been done to reveal the underlying electronic structure of this material system, comparing to the huge amount of investigations on the material synthesis. The effective mass of the valance band is one of the most important physical parameters which plays a dominant role in charge transport and photovoltaic phenomena. In pristine CsPbBr₃, the Fröhlich polarons associated with the Pb–Br stretching modes are proposed to be responsible for the effective mass renormalization. In this regard, it would be very interesting to explore the electronic structure in doped LHPs. Here, we report high-resolution angle-resolved photoemission spectroscopy (ARPES) studies on both pristine and Cl-doped CsPbBr₃. The experimental band dispersions are extracted from ARPES spectra along both $$\overline{\Gamma}$$–$$\overline{M}$$–$$\overline{\Gamma}$$ and $$\overline{X}$$–$$\overline{M}$$–$$\overline{X}$$ high symmetry directions. DFT calculations are performed and directly compared with the ARPES data. Our results have revealed the band structure of Cl-doped CsPbBr₃ for the first time, which have also unveiled the effective mass renormalization in the Cl-doped CsPbBr₃ compound. Doping dependent measurements indicate that the chlorine doping could moderately tune the renormalization strength. These results will help understand the physical properties of LHPs as a function of doping.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: Chinese Academy of Sciences (CAS); Fundamental Research Funds for the Central Universities; USDOE Office of Science (SC)
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 2406825
• Journal Information: Chinese Physics B, Journal Name: Chinese Physics B Journal Issue: 5 Vol. 33; ISSN 1674-1056
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
effective mass
electronic structure
lead halide perovskites