講演情報
[21a-D903-10]Light illumination stability improvement for Sn-Pb mixed perovskite solar cells through surface modification
〇(DC)Yulu He1,2, Md. Emrul Kayesh1, Muhammad Monirul Islam2, Wasif Chowdhury1, Towhid Hossain Chowdhury1, Md. Abdul Karim1, Siliang Cao1,2, Takeaki Sakurai2, Ashraful Islam1 (1.NIMS, 2.Univ. of Tsukuba)
キーワード：
Sn-Pb mixed Perovskite solar cells、High efficiency、Stability
Perovskite solar cells (PSCs) have attracted much attention because of the fast progress of their power conversion efficiency (PCE), from 3.8% to 25.7% in the past 14 years. However, the highest efficiency of the PSCs is close to the theoretical efficiency limit (around 31 %) of the single junction PSCs. To overcome the efficiency limit of the single junction PSCs. All perovskite tandem solar cells should be focused on. Sn-Pb mixed PSCs are the key points for achieving all perovskite tandem solar cells. Recently, the best Sn-Pb mixed PSCs have achieved over 23 % efficiency. However, the stability of the Sn-Pb mixed PSCs is relatively low compared to pure Pb-based PSCs, which limits the practical use of the tandem solar cells.
Suppression of Sn2+ oxidation is one of the most crucial points for achieving high performance and stability of Sn-Pb mixed PSCs. According to recent studies, the Sn2+ oxidation is more dominant on the perovskite surface.[3] The oxidation of Sn2+ even occurs during the formation of perovskite film in the inert atmosphere. Therefore, suppression of Sn oxidation of the Sn-Pb mixed perovskite surface is important to achieve highly stable Sn-Pb mixed PSCs.
In this work, a Pb-contained solution was used for perovskite surface treatment, leading to improved light illumination stability of Sn-Pb mixed perovskite solar cells.
Without surface modification, Sn2+ oxidation may easier occur on the perovskite surface. After Pb2+-contained solution surface modification, the Pb2+ ratio increases due to the introduction of the Pb2+, which can suppress the oxidation of the Sn2+ on the perovskite surface. Therefore, the surface modified PSCs by the Pb2+-contained solution achieved better stability.
Suppression of Sn2+ oxidation is one of the most crucial points for achieving high performance and stability of Sn-Pb mixed PSCs. According to recent studies, the Sn2+ oxidation is more dominant on the perovskite surface.[3] The oxidation of Sn2+ even occurs during the formation of perovskite film in the inert atmosphere. Therefore, suppression of Sn oxidation of the Sn-Pb mixed perovskite surface is important to achieve highly stable Sn-Pb mixed PSCs.
In this work, a Pb-contained solution was used for perovskite surface treatment, leading to improved light illumination stability of Sn-Pb mixed perovskite solar cells.
Without surface modification, Sn2+ oxidation may easier occur on the perovskite surface. After Pb2+-contained solution surface modification, the Pb2+ ratio increases due to the introduction of the Pb2+, which can suppress the oxidation of the Sn2+ on the perovskite surface. Therefore, the surface modified PSCs by the Pb2+-contained solution achieved better stability.