Corresponding Author

Mei-Dan Ye(mdye@xmu.edu.cn)


2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,9′-spirobifluorene (Spiro-OMeTAD) is the most widely used hole transport material in perovskite solar cells (PSCs). However, its oxidation in the air takes a long time and results in the attack of perovskite by water. In this regard, we performed the oxidation process of Spiro-OMeTAD in oxygen, where perovskite can be protected from water, guaranteeing the integrity of perovskite. It was demonstrated that the champion Spiro-OMeTAD based CsPbIBr2 PSCs after oxygen oxidation achieved a 7.19% power conversion efficiency (PCE), showing a higher PCE than 6.29% of the champion device oxidized in air. A series of electrochemical characterization methods were applied to investigate the performances of the different cell devices under different oxidation conditions. It was revealed that the oxygen oxidation enabled to enhance the hole conductivity of Spiro-OMeTAD, reduce the charge recombination and improve the charge transfer efficiency in PSCs. Moreover, the device with oxygen oxidation had a higher average efficiency and greater stability. This method makes the devices have better repeatability, which provides a reliable idea for the commercial development of PSCs.

Graphical Abstract


perovskite, Spiro-OMeTAD, rapid oxidation, CsPbIBr2

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