[14a-A402-1~9] 12.5 Organic solar cells

[14a-A402-6] Direct observation at the interface of the charge transfer of tin-based perovskite solar cells with mixed halogen

〇Yihuang Wang¹, Mayu Motohashi¹, Xiangtao Zou¹, Haru Kimata¹, Dong Xue¹, Akinori Saeki², Tomoya Nakamura³, Atsushi Wakamiya³, Kazuhiro Marumoto^1,4 (1.Univ. of Tsukuba, 2.Osaka Univ., 3.Kyoto Univ., 4.TREMS)

Keywords:perovskite solar cell, ESR

Tin-based perovskite solar cells (Sn-based PSC) have attracted tremendous attention as a next-generation solar cell due to their advantages such as flexibility, low-cost fabrication, and non-toxicity. However, problems such as low efficiency (~11%), low open-circuit voltage, and easy oxidation of Sn (II) remain to be solved. In order to make the solar cells more stable and to prevent Sn (II) from oxidation, mixed halogen and tin powder have been added to perovskite layer. In this study, we added bromide into perovskite layer along with tin powder, and fabricated layered thin-film samples using PSC materials. We investigated the charge states in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/perovskite layered thin-film samples by electron spin resonance (ESR) spectroscopy. As a result, we observed changes in the ESR signals of PEDOT:PSS with the adding of Bromine to the perovskite layer.