Issue

Vol. 12 (2020)

Low-Temperature Growing Anatase TiO2/SnO2 Multi-dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells

https://doi.org/10.1007/s40820-020-0379-5
Linsheng Huang
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Xiaowen Zhou
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Rui Xue
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Pengfei Xu
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Siliang Wang
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Chao Xu
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Wei Zeng
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China
Yi Xiong
Science and Technology Institute, Hubei Key Laboratory of Biomass Fibers and Eco‑Dyeing and Finishing, Wuhan Textile University, Wuhan 430073, People’s Republic of China
Hongqian Sang
School of Physics and Technology, MOE Key Laboratory of Artificial Micro‑ and Nano‑Structures and Center for Electron Microscopy, Wuhan University, Wuhan 430072, People’s Republic of China
Dong Liang
National Engineering Research Center for Agro‑Ecological Big Data Analysis and Application, School of Electronics and Information Engineering, Anhui University, No. 111 Jiulong Road, Hefei 230601, People’s Republic of China

Corresponding Author: Yi Xiong

xiong@wtu.edu.cn

Nano-Micro Letters, Vol. 12 (2020), Article Number: 44

Abstract

A multi-dimensional conductive heterojunction structure, composited by TiO2, SnO2, and Ti3C2TX MXene, is facilely designed and applied as electron transport layer in efficient and stable planar perovskite solar cells. Based on an oxygen vacancy scramble effect, the zero-dimensional anatase TiO2 quantum dots, surrounding on two-dimensional conductive Ti3C2TX sheets, are in situ rooted on three-dimensional SnO2 nanoparticles, constructing nanoscale TiO2/SnO2 heterojunctions. The fabrication is implemented in a controlled low-temperature anneal method in air and then in N2 atmospheres. With the optimal MXene content, the optical property, the crystallinity of perovskite layer, and internal interfaces are all facilitated, contributing more amount of carrier with effective and rapid transferring in device. The champion power conversion efficiency of resultant perovskite solar cells achieves 19.14%, yet that of counterpart is just 16.83%. In addition, it can also maintain almost 85% of its initial performance for more than 45 days in 30–40% humidity air; comparatively, the counterpart declines to just below 75% of its initial performance.


Highlights:


1 Nanoscale multi-dimensional heterojunctions in situ grow at the edge of two-dimensional MXene conductive network.
2 A controlled anneal procedure in 150 °C is for preparing anatase TiO2/SnO2 heterojunctions with oxygen vacancy scramble effect.
3 The perovskite solar cells achieve high power conversion efficiency and high moisture-resistance stability.

Keywords

In situ fabrication Multi-dimensional heterojunction Oxygen vacancy scramble effect Electron transport layer Perovskite solar cells
Huang, Linsheng, Xiaowen Zhou, Rui Xue, Pengfei Xu, Siliang Wang, Chao Xu, Wei Zeng, Yi Xiong, Hongqian Sang, and Dong Liang. 2020. “Low-Temperature Growing Anatase TiO2/SnO2 Multi-Dimensional Heterojunctions at MXene Conductive Network for High-Efficient Perovskite Solar Cells”. Nano-Micro Letters 12 (January):44. https://doi.org/10.1007/s40820-020-0379-5.
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