Plasmon‐Enhanced Perovskite Solar Cells with Efficiency Beyond 21 %: The Asynchronous Synergistic Effect of Water and Gold Nanorods

• Published in: ChemPlusChem (Weinheim, Germany) Vol. 86; no. 2; pp. 291 - 297
• Main Authors: Gao, Yifeng, Zhang, Jiaoxia, Zhang, Zhihao, Li, Zicheng, Xiong, Qiu, Deng, Longhui, Zhou, Qin, Meng, Lingyi, Du, Yitian, Zuo, Tao, Yu, Yaming, Lan, Zhang, Gao, Peng
• Format: Journal Article
• Language: English
• Published: Germany 01.02.2021
• Subjects: Gold; localized surface plasmon resonance; nanostructures; perovskites; solar cells; perovskites; Gold; solar cells; localized surface plasmon resonance; nanostructures
• ISSN: 2192-6506; 2192-6506
• DOI: 10.1002/cplu.202000792

Although perovskite films have excellent extinction coefficients, further increase of the light‐absorbing capacity by increasing the thickness of the active layer is always required in perovskite solar cells (PSCs). However, to maintain the morphology quality of the perovskite layer, the film thickness is subject to certain restrictions. To increase the light absorbance without significantly inflating the perovskite film while keeping the high quality of the perovskite film, herein, we added an aqueous solution of gold nanorods (AuNRs) to the perovskite precursor solution via a so‐called asynchronous synergistic effect (ASE) strategy of water and AuNR. The former improves the quality of the perovskite film during the crystallization process to reduce defect density and enhance carrier mobility. Simultaneously, the latter increases the light absorption of the perovskite layer through the localized surface plasmon resonance (LSPR) effect when the device is exposed to light. We show that the ASE strategy leads to an excellent power conversion efficiency (PCE) of 21.73 % and outstanding long‐term stability, which can retain 95 % of its initial PCE after storage for three months in an air atmosphere. Out of sync but working well: Addition of an aqueous solution of gold nanorods to the perovskite precursor resulted in a so‐called asynchronous synergistic effect (ASE), which significantly improves the quality of the film and the light absorption of the perovskite layer. The fill factor of the device has increased from 78 % to 82 %, and the current of the device increased from 22.98 to 23.72 mA cm−2. PCE of champion devices is 21.73 %, and retain 95 % of its initial PCE for three months in air.