Optimization of Charge Extraction and Interconnecting Layers for Highly Efficient Perovskite/Organic Tandem Solar Cells with High Fill Factor

• Published in: Advanced materials (Weinheim) Vol. 36; no. 49; pp. e2410692 - n/a
• Main Authors: Wu, Xin, Zhang, Dong, Liu, Baoze, Wang, Yan, Wang, Xue, Liu, Qi, Gao, Danpeng, Wang, Ning, Li, Bo, Wang, Lina, Yu, Zexin, Li, Xintong, Xiao, Shuang, Li, Nan, Stolterfoht, Martin, Lin, Yen‐Hung, Yang, Shangfeng, Zeng, Xiao Cheng, Zhu, Zonglong
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.12.2024
• Subjects: charge extraction; Energy conversion efficiency; Heterojunctions; Illumination; interconnecting layer; Optimization; perovskite/organic tandem solar cells; Perovskites; Phosphonic acids; Photovoltaic cells; Self-assembly; Solar cells; stability; Thickness; perovskite/organic tandem solar cells; charge extraction; performance; interconnecting layer; stability
• ISSN: 0935-9648; 1521-4095; 1521-4095
• DOI: 10.1002/adma.202410692

Perovskite/organic tandem solar cells (POTSCs) have garnered significant attention due to their potential for achieving high photovoltaic (PV) performance. However, the reported power conversion efficiencies (PCEs) and fill factors (FFs) are still subpar due to the challenges associated with charge extraction in the organic bulk‐heterojunction (BHJ) and significant energy losses in the interconnecting layers (ICLs). Here, a quaternary organic BHJ blend is developed to enhance the charge extraction in the organic subcell, contributing to an increased FF of ≥78% under 1 sun illumination and even more under lower illumination intensities. Meanwhile, energy losses in the ICLs are reduced via the incorporation of a self‐assembly monolayer (SAM), (4‐(3,6‐Dimethyl‐9H‐carbazol‐9‐yl)butyl)phosphonic acid (Me‐4PACz), in organic BHJ to form a MoOx/SAM interface and the thorough control of the MoOx thickness to suppress parasitic absorption. The resultant POTSCs achieve a remarkable PCE of 25.56% (certified: 24.65%), with a record FF of 83.62%, which is among the highest PCEs of POTSCs and the highest FF of all types of perovskite‐based tandem solar cells (TSCs) till now. This work proves the optimization of charge extraction and ICLs are effective strategies to promote the performance of POTSCs to surpass other solution‐processed perovskite‐based TSCs in the near future. This work developshighly efficient perovskite/organic tandem solar cells (POTSC) via the simultaneous optimization of quaternary organic BHJ blend, and reduction of optical and electrical losses of interconnecting layers via self‐assembly monolayer. The resultant POTSCs achieve a remarkable power conversion efficiency (PCE) of 25.56% (certified: 24.65%), with a record fill factor (FF) of 83.62% of all types of perovskite‐based tandem solar cells (TSCs) till now.