Interfacial Engineering for High-Efficiency Nanorod Array-Structured Perovskite Solar Cells

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

doi:10.1021/acsami.9b07610

Interfacial Engineering for High-Efficiency Nanorod Array-Structured Perovskite Solar Cells

ACS Appl Mater Interfaces. 2019 Sep 18;11(37):33770-33780. doi: 10.1021/acsami.9b07610. Epub 2019 Aug 14.

Authors

Bingbing Cao¹, Haoran Liu¹, Longkai Yang¹, Xin Li¹, Hu Liu^{2

3}, Pei Dong⁴, Xianmin Mai⁵, Chuanxin Hou⁶, Ning Wang⁷, Jiaoxia Zhang^{3

8}, Jincheng Fan⁹, Qiang Gao¹⁰, Zhanhu Guo³

Affiliations

¹ Pen-Tung Sah Institute of Micro-Nano Science and Technology , Xiamen University , Xiamen 361005 , China.
² Key Laboratory of Materials Processing and Mold (Zhengzhou University), Ministry of Education; National Engineering Research Center for Advanced Polymer Processing Technology , Zhengzhou University , Zhengzhou 450002 , China.
³ Integrated Composites Laboratory (ICL), Department of Chemical & Biomolecular Engineering , University of Tennessee , Knoxville , Tennessee 37996 , United States.
⁴ Department of Mechanical Engineering , George Mason University , Fairfax , Virginia 22030 , United States.
⁵ School of Urban Planning and Architecture , Southwest Minzu University , Chengdu 610041 , China.
⁶ School of Materials Science and Engineering , North University of China , Taiyuan 030051 , China.
⁷ State Key Laboratory of Marine Resource Utilization in South China Sea , Hainan University , Haikou 570228 , China.
⁸ School of Materials Science and Engineering , Jiangsu University of Science and Technology , Zhenjiang 212003 , China.
⁹ College of Materials Science and Engineering , Changsha University of Science and Technology , Changsha 410114 , China.
¹⁰ Scanning Probe Microscopy Group, Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , PO Box 2008, Oak Ridge , Tennessee 37831 , United States.

PMID: 31366197
DOI: 10.1021/acsami.9b07610

Abstract

TiO₂ nanorod (NR) array for perovskite solar cells (PSCs) has attained great importance due to its superb power conversion efficiency (PCE) compared to that of the traditional mesoporous TiO₂ film. A TiO₂ compact layer for the growth of TiO₂ NR array via spin-coating cannot meet the requirements for efficient NR-based PSCs. Herein, we have developed and demonstrated the insertion of a bifunctional extrathin TiO₂ interlayer (5 nm) by atomic layer deposition (ALD) at the interface of the fluorine-doped tin oxide (FTO)/TiO₂ compact layer to achieve alleviated electron exchange and a reduced energetic barrier. Thus, an accelerated extraction of electrons from TiO₂ NR arrays via the compact layer and their transfer to the FTO substrate can improve the PSC efficiency. The thickness of the spin-coated TiO₂ compact layer on the ALD-deposited TiO₂ 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 study demonstrating the superiority of TiO₂-NR-based PSCs withstanding the dry heat and thermal cycling tests. The results are of great importance for the preparation of efficient and durable PSCs for real-world applications.

Keywords: TiO nanorod; atomic layer deposition; compact layer; depletion region; perovskite solar cells.