Interfacial Engineering for High Efficiency Nanorod Array Structured Perovskite Solar Cells

Cao, Bingbing; Liu, Haoran; Yang, Longkai; Li, Xin; Liu, Hu; Dong, Pei; Mai, Xianmin; Hou, Chuanxin; Wang, Ning; Zhang, Jiaoxia; Fan, Jincheng; Gao, Qiang; Guo, Zhanhu

doi:10.1021/acsami.9b07610

DOE OSTI · 1546536

Interfacial Engineering for High Efficiency Nanorod Array Structured Perovskite Solar Cells

Cao, Bingbing·Liu, Haoran·Yang, Longkai·Li, Xin·Liu, Hu·Dong, Pei·Mai, Xianmin·Hou, Chuanxin·Wang, Ning·Zhang, Jiaoxia·Fan, Jincheng·Gao, Qiang·Guo, Zhanhu

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Abstract

TiO 2 nanorod (NR) array for perovskite solar cells (PSCs) has attached great importance due to superb power conversion efficiency (PCE) compared to traditional mesoporous TiO 2 film. A TiO 2 compact layer for the growth of TiO 2 NR array via spin-coating cannot meet the requirements for efficient NR based PSCs. Herein we have developed and demonstrated inserting an bifunctional extra-thin TiO 2 interlayer (5 nm) by atomic layer deposition (ALD) at the interface of FTO/TiO 2 compact layer to achieve an alleviated electron exchange and a reduced energetic barrier. Thus, an accelerated extraction of electrons from TiO 2 NR arrays via the compact layer to FTO substrate is ready for improving the PSC efficiency. The thickness of the spin-coated TiO 2 compact layer on the ALD-deposited TiO 2 layer is spontaneously optimized. Finally, an outstanding efficiency of 20.28% has been achieved from a champion PSC with negligible hysteresis and high reliability. To the best of our knowledge, this is the first time to demonstrate the superiority of TiO 2 -NR based PSCs withstanding in dry heat and thermal cycling tests. The results are of great importance for the preparation of efficient and durable PSCs for our real-world applications.

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Cao, Bingbing, Liu, Haoran, Yang, Longkai, Li, Xin, Liu, Hu, Dong, Pei, Mai, Xianmin, Hou, Chuanxin, Wang, Ning, Zhang, Jiaoxia, Fan, Jincheng, Gao, Qiang, Guo, Zhanhu. 2019-07-31. Interfacial Engineering for High Efficiency Nanorod Array Structured Perovskite Solar Cells. https://doi.org/10.1021/acsami.9b07610

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