High-Performance Deep Ultraviolet Photodetector Based on a One-Dimensional Lead-Free Halide Perovskite CsCu2I3 Film with High Stability

• Published in: The journal of physical chemistry letters Vol. 11; no. 16; pp. 6880 - 6886
• Main Authors: Yang, Jie, Kang, Wei, Liu, Zhengzheng, Pi, Mingyu, Luo, Lin-Bao, Li, Chen, Lin, Hao, Luo, Zhongtao, Du, Juan, Zhou, Miao, Tang, Xiaosheng
• Format: Journal Article
• Language: English
• Published: American Chemical Society 20.08.2020
• Subjects: Physical Insights into Materials and Molecular Properties
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.0c01832

Lead halide perovskites have received much attention in the field of optoelectronic devices. However, the environment-unfriendly nature and intrinsic instability of these perovskites hamper their commercial applications. In this work, one novel one-dimensional lead-free halide perovskite with high stability, CsCu2I3, was prepared via an antisolvent-assisted crystallization method. The prepared CsCu2I3 bears a high exciton binding energy of ∼105 meV and a high photoluminescence quantum yield of 12.3%. We fabricated a deep ultraviolet photodetector based on a CsCu2I3 film that is nearly blind to 405 nm visible light but is sensitive to 265 and 365 nm illumination. The device exhibits excellent reproducibility and a high I light/I dark ratio of 22 under 265 nm illumination. Furthermore, the responsivity, specific detectivity, and external quantum efficiency are as high as 22.1 mA/W, 1.2 × 1011 Jones, and 10.3% under a light density of 0.305 mW/cm2, respectively. These findings demonstrate that CsCu2I3 perovskites should have great potential for future optoelectronics.