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Updated: Mar 2, 2026
Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
Stable and conductive lead halide perovskites facilitated by X-type ligands
Longfei Ruan1, Wei Shen, Aifei Wang
1Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing National Laboratory of Microstructures, Collaborative Innovation Center of Chemistry for Life Sciences, Nanjing University, Nanjing, Jiangsu 210093, People's Republic of China. sw1231@gmail.com dengz@nju.edu.cn.
Abstract:
Lead halide perovskites exhibit outstanding optoelectronic and optical properties. However, some applications of perovskites are hindered by their instability in polar environments; thus, how to balance stability with conductivity is a great challenge. Here, we report a new approach of using X-type ligands to address this issue. Surface treatments containing multi-step ligand exchanges and ion filling were necessary to obtain X-type ligand-protected perovskites. Performances of this material show that: (1) the crystal structure of perovskites is stable in ethanol; (2) surface defects can be fixed by a photoactivation process and photoluminescence intensity can be enhanced to 136%; and (3) electronic devices fabricated from such materials show stabilility even after washing with ethanol. X-type ligand-protected perovskites with high stability and good conductivity are promising new materials for wide applications in electronic and optoelectronics devices.
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