摘要
Achieving long-term operational stability at a high efficiency level for perovskite solar cells is the most challenging issue toward commercialization of this emerging photovoltaic technology. Here, we investigated the cooperation of a Lewis base and a Lewis acid by combining commercial bis-PCBM mixed isomers as the Lewis acid in the antisolvent and N-(4-bromophenyl)thiourea (BrPh-ThR) as the Lewis base in the perovskite solution precursor. The combination of the Lewis base and the Lewis acid synergistically passivates Pb 2+ and PbX 3- antisite defects, enlarges the perovskite grain size, and improves charge-carrier separation and transport, leading to improved device efficiency from 19.3% to 21.7%. In addition, this Lewis base and acid combination also suppresses moisture incursion and passivates pinholes generated in the hole-transporting layer. The unsealed devices remained at 93% of the initial efficiency value in ambient air (10-20% relative humidity) after 3600 h at 20-25 °C and dropped by 10% after 1500 h under continuous operation at 1-sun illumination and 55 °C in nitrogen with maximum power-point tracking.
源语言 | 英语 |
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页(从-至) | 3480-3490 |
页数 | 11 |
期刊 | Energy and Environmental Science |
卷 | 11 |
期 | 12 |
DOI | |
出版状态 | 已出版 - 12月 2018 |
已对外发布 | 是 |