Atomically resolved edges and defects in lead halide perovskites

Yuan, Biao [University of Antwerp (Belgium); South China University of Technology, Guangzhou (China)] (ORCID:0000000190853928); Wang, Zeyu [ShanghaiTech University (China)]; Zhang, Shuchen [University of Science and Technology of China, Hefei (China)]; Hofer, Christoph [University of Antwerp (Belgium)]; Gao, Chuang [University of Antwerp (Belgium)]; Chennit, Tamazouzt [University of Antwerp (Belgium)]; Shi, Hongsheng [ShanghaiTech University (China)]; Wu, Xiaoyan [ShanghaiTech University (China)] (ORCID:0009000083283680); Han, Yu [South China University of Technology, Guangzhou (China)] (ORCID:0000000314621118); Dou, Letian [Purdue University, West Lafayette, IN (United States); Emory University, Atlanta, GA (United States)] (ORCID:0000000164118591); Yu, Yi [ShanghaiTech University (China)] (ORCID:0000000343265992); Pennycook, Timothy J. [University of Antwerp (Belgium)] (ORCID:0000000200086516)

doi:10.1038/s41586-025-09693-6

DOE OSTI · 3366456

Atomically resolved edges and defects in lead halide perovskites

Yuan, Biao [University of Antwerp (Belgium); South China University of Technology, Guangzhou (China)] (ORCID:0000000190853928)·Wang, Zeyu [ShanghaiTech University (China)]·Zhang, Shuchen [University of Science and Technology of China, Hefei (China)]·Hofer, Christoph [University of Antwerp (Belgium)]·Gao, Chuang [University of Antwerp (Belgium)]·Chennit, Tamazouzt [University of Antwerp (Belgium)]·Shi, Hongsheng [ShanghaiTech University (China)]·Wu, Xiaoyan [ShanghaiTech University (China)] (ORCID:0009000083283680)·Han, Yu [South China University of Technology, Guangzhou (China)] (ORCID:0000000314621118)·Dou, Letian [Purdue University, West Lafayette, IN (United States); Emory University, Atlanta, GA (United States)] (ORCID:0000000164118591)·Yu, Yi [ShanghaiTech University (China)] (ORCID:0000000343265992)·Pennycook, Timothy J. [University of Antwerp (Belgium)] (ORCID:0000000200086516)

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Abstract

Although edges and defects constitute only a small fraction of crystalline materials, they exert an outsized impact on a material′s properties. Organic–inorganic halide perovskites are promising next-generation semiconductor materials with superior cost effectiveness and interesting optoelectronic properties. However, clear images of their edges have remained challenging to obtain owing to their extreme sensitivity. Using truly high-speed ultralow-dose four-dimensional scanning transmission electron microscopy with dose fractionation, we perform ptychography at, to our knowledge, the lowest-dose atomic resolution to date, revealing not only the detailed atomic structure of the edges of a halide perovskite but also their structural dynamics. Here, a majority methylammonium (MA) and iodine (I) edge termination is observed in methylammonium lead iodide (MAPbI 3 ), and the damage rate of its edges and internal defects is found to depend on the concentration and type of vacancies present, with a preponderance of I vacancies in particular correlating with higher rates of damage.

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Yuan, Biao [University of Antwerp (Belgium); South China University of Technology, Guangzhou (China)] (ORCID:0000000190853928), Wang, Zeyu [ShanghaiTech University (China)], Zhang, Shuchen [University of Science and Technology of China, Hefei (China)], Hofer, Christoph [University of Antwerp (Belgium)], Gao, Chuang [University of Antwerp (Belgium)], Chennit, Tamazouzt [University of Antwerp (Belgium)], Shi, Hongsheng [ShanghaiTech University (China)], Wu, Xiaoyan [ShanghaiTech University (China)] (ORCID:0009000083283680), Han, Yu [South China University of Technology, Guangzhou (China)] (ORCID:0000000314621118), Dou, Letian [Purdue University, West Lafayette, IN (United States); Emory University, Atlanta, GA (United States)] (ORCID:0000000164118591), Yu, Yi [ShanghaiTech University (China)] (ORCID:0000000343265992), Pennycook, Timothy J. [University of Antwerp (Belgium)] (ORCID:0000000200086516). 2025-10-29. Atomically resolved edges and defects in lead halide perovskites. https://doi.org/10.1038/s41586-025-09693-6

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