High-Performing Quasi-2D Perovskite Photodetectors with Efficient Charge Transport Network Built from Vertically Orientated and Evenly Distributed 3D-Like Phases

作者：Li, Bolun; Huang, Xi; Wu, Xiang; Zuo, Qiong; Cao, Yunhao; Zhu, Qi; Li, Yaohui; Xu, Yuanhuan; Zheng, Guanhaojie^*; Chen, Dongcheng; Zhu, Xu-Hui; Huang, Fei; Zhen, Hongyu; Hou, Lintao; Qing, Jian^*; Cai, Wanzhu^*

来源：Advanced Functional Materials, 2023, 33(28).

DOI：10.1002/adfm.202300216

• charge transport
• hybrid low-dimensional phase structure
• photodetectors
• quasi-2D perovskites
• specific detectivity

Quasi-two-dimensional (Q-2D) perovskites are emerging as one of the most promising materials for photodetectors. However, a significant challenge to Q-2D perovskites for photodetection is their insufficient charge transport ability, which is mainly attributed to their hybrid low-dimensional n-phase structure. This study demonstrates that evenly-distributed 3D-like phases with vertical orientation throughout the film can greatly facilitate charge transport and suppress charge recombination, outperforming the prevalent phase structure with a vertical dimension gradient. Based on such a phase structure, a Q-2D Ruddlesden-Popper perovskite self-powered photodetector achieving a combination of exceptional figures-of-merit is realized, including a responsivity of 0.45 AW(-1), a peak specific detectivity of 2.3 x 10(13) Jones, a 156 dB linear dynamic range, and a rise/fall time of 2.89 mu s/1.93 mu s. The desired phase structure is obtained by utilizing a double-hole transport layer (HTL), combining hydrophobic PTAA and hydrophilic PEDOT: PSS. Besides, the dependence of the hybrid low-dimensional phase structure is also identified on the surface energy of the buried HTL substrate. This study gives insight into the correlation between Q-2D perovskites' phase structure and performance, providing a valuable design guide for Q-2D perovskite-based photodetectors.

• 单位
  中国科学院