Dopant-Free Organic Hole-Transporting Material for Efficient and Stable Inverted All-Inorganic and Hybrid Perovskite Solar Cells

Authors：Jiang, Kui; Wang, Jing; Wu, Fei; Xue, Qifan^*; Yao, Qin; Zhang, Jianquan; Chen, Yihuang; Zhang, Guangye; Zhu, Zonglong; Yan, He; Zhu, Linna^*; Yip, Hin-Lap^*

Source：Advanced Materials, 2020, 32(16): 1908011.

DOI：10.1002/adma.201908011

• all-inorganic perovskites
• device stability
• hole-transporting materials
• inverted perovskite solar cells
• passivation effect

Designing new hole-transporting materials (HTMs) with desired chemical, electrical, and electronic properties is critical to realize efficient and stable inverted perovskite solar cells (PVSCs) with a p-i-n structure. Herein, the synthesis of a novel 3D small molecule named TPE-S and its application as an HTM in PVSCs are shown. The all-inorganic inverted PVSCs made using TPE-S, processed without any dopant or post-treatment, are highly efficient and stable. Compared to control devices based on the commonly used HTM, PEDOT:PSS, devices based on TPE-S exhibit improved optoelectronic properties, more favorable interfacial energetics, and reduced recombination due to an improved trap passivation effect. As a result, the all-inorganic CsPbI2Br PVSCs based on TPE-S demonstrate a remarkable efficiency of 15.4% along with excellent stability, which is the one of the highest reported values for inverted all-inorganic PVSCs. Meanwhile, the TPE-S layer can also be generally used to improve the performance of organic/inorganic hybrid inverted PVSCs, which show an outstanding power conversation efficiency of 21.0%, approaching the highest reported efficiency for inverted PVSCs. This work highlights the great potential of TPE-S as a simple and general dopant-free HTM for different types of high-performance PVSCs.

• Institution
  西南大学