Effective Carrier-Concentration Tuning of SnO2 Quantum Dot Electron-Selective Layers for High-Performance Planar Perovskite Solar Cells

Guang Yang; Cong Chen; Fang Yao; Zhiliang Chen; Qi Zhang; Xiaolu Zheng; Junjie Ma; Hongwei Lei; Pingli Qin; Liangbin Xiong; Weijun Ke; Gang Li; Yanfa Yan; Guojia Fang

doi:10.1002/adma.201706023

Effective Carrier-Concentration Tuning of SnO₂ Quantum Dot Electron-Selective Layers for High-Performance Planar Perovskite Solar Cells

Adv Mater. 2018 Apr;30(14):e1706023. doi: 10.1002/adma.201706023. Epub 2018 Feb 27.

Authors

Guang Yang^{1

2}, Cong Chen^{1

3}, Fang Yao¹, Zhiliang Chen¹, Qi Zhang¹, Xiaolu Zheng¹, Junjie Ma¹, Hongwei Lei¹, Pingli Qin^{1

2}, Liangbin Xiong¹, Weijun Ke¹, Gang Li², Yanfa Yan³, Guojia Fang¹

Affiliations

¹ Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China.
² Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
³ Department of Physics and Astronomy and Wright Center for Photovoltaics Innovation and Commercialization, The University of Toledo, Toledo, OH, 43606, USA.

PMID: 29484722
DOI: 10.1002/adma.201706023

Abstract

The carrier concentration of the electron-selective layer (ESL) and hole-selective layer can significantly affect the performance of organic-inorganic lead halide perovskite solar cells (PSCs). Herein, a facile yet effective two-step method, i.e., room-temperature colloidal synthesis and low-temperature removal of additive (thiourea), to control the carrier concentration of SnO₂ quantum dot (QD) ESLs to achieve high-performance PSCs is developed. By optimizing the electron density of SnO₂ QD ESLs, a champion stabilized power output of 20.32% for the planar PSCs using triple cation perovskite absorber and 19.73% for those using CH₃ NH₃ PbI₃ absorber is achieved. The superior uniformity of low-temperature processed SnO₂ QD ESLs also enables the fabrication of ≈19% efficiency PSCs with an aperture area of 1.0 cm² and 16.97% efficiency flexible device. The results demonstrate the promise of carrier-concentration-controlled SnO₂ QD ESLs for fabricating stable, efficient, reproducible, large-scale, and flexible planar PSCs.

Keywords: SnO2 QD; carrier concentration; flexible; large-scale; planar perovskite solar cells.