Neglected acidity pitfall:boric acid-anchoring hole-selective contact for perovskite solar cells  

作　　者：Huanxin Guo Cong Liu Honglong Hu Shuo Zhang Xiaoyu Ji Xiao-Ming Cao Zhijun Ning Wei-Hong Zhu He Tian Yongzhen Wu 

机构地区：[1]Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering,Feringa Nobel Prize Scientist Joint Research Center,Institute of Fine Chemicals,Frontiers Science Center for Materiobiology and Dynamic Chemistry,School of Chemistry and Molecular Engineering,East China University of Science and Technology,Shanghai 200237,China [2]School of Physical Science and Technology,Shanghai Tech University,Shanghai 201210,China

出　　处：《National Science Review》2023年第5期215-225,共11页国家科学评论（英文版）

基　　金：supported by the National Natural Science Foundation of China (22179037, 22022302 and 92045303);Program of Introducing Talents of Discipline to Universities (B16017);Innovation Program of Shanghai Municipal Education Commission (2021-01-07-00-02-E00107);Shanghai Municipal Science and Technology Major Project (2018SHZDZX03 and21JC1401700)。

摘　　要：The spontaneous formation of self-assembly monolayer(SAM) on various substrates represents an effective strategy for interfacial engineering of optoele ctronic devices.Hole-selective SAM is becoming popular among high-performance inverted perovskite solar cells(PSCs),but the presence of strong acidic anchors(such as-PO_(3)H_(2)) in state-of-the-art SAM is detrimental to device stability.Herein,we report for the first time that acidity-weakened boric acid can function as an alternative anchor to construct efficient SAM-based hole-sele ctive contact(HSC) for PSCs.Theoretical calculations reve al that boric acid spontaneously chemisorbs onto indium tin oxide(ITO) surface with oxygen vacancies facilitating the adsorption progress.Spectroscopy and electrical measurements indicate that boric acid anchor significantly mitigates ITO corrosion.The excess boric acid containing molecules improves perovskite deposition and results in a coherent and well-passivated bottom interface,which boosts the fill factor(FF) performance for a variety of perovskite compositions.The optimal boric acid-anchoring HSC(MTPA-BA) can achieve power conversion efficiency close to 23% with a high FF of 85.2%.More importantly,the devices show improved stability:90% of their initial efficiency is retained after 2400 h of storage(ISOS-D-1) or 400 h of operation(ISOS-L-1),which are 5-fold higher than those of phosphonic acid SAM-based devices.Acidity-weakened boric acid SAMs,which are friendly to ITO,exhibits well the great potential to improve the stability of the interface as well as the device.

关 键 词：perovskite solar cells hole-selective contact boric acid anchor acid-induced degradation long-term stability 

分 类 号：TM914.4[电气工程—电力电子与电力传动] TB34[一般工业技术—材料科学与工程]