Quantification of Efficiency Losses Due to Mobile Ions in Perovskite Solar Cells via Fast Hysteresis Measurements. Issue 4 (17th January 2022)

• Record Type: Journal Article
• Authors: Le Corre, Vincent M.; Diekmann, Jonas; Peña-Camargo, Francisco; Thiesbrummel, Jarla; Tokmoldin, Nurlan; Gutierrez-Partida, Emilio; Peters, Karol Pawel; Perdigón-Toro, Lorena; Futscher, Moritz H.; Lang, Felix; Warby, Jonathan; Snaith, Henry J.; Neher, Dieter; Stolterfoht, Martin
• Is Part Of: Solar RRL. Volume 6:Issue 4(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-17
• Subjects: hysteresis -- mobile ions -- perovskite solar cells; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202100772
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Perovskite semiconductors differ from most inorganic and organic semiconductors due to the presence of mobile ions in the material. Although the phenomenon is intensively investigated, important questions such as the exact impact of the mobile ions on the steady‐state power conversion efficiency (PCE) and stability remain. Herein, a simple method is proposed to estimate the efficiency loss due to mobile ions via "fast‐hysteresis" measurements by preventing the perturbation of mobile ions out of their equilibrium position at fast scan speeds ( ≈ 1000 V s −1 ). The "ion‐free" PCE is between 1% and 3% higher than the steady‐state PCE, demonstrating the importance of ion‐induced losses, even in cells with low levels of hysteresis at typical scan speeds ( ≈ 100 mV s −1 ). The hysteresis over many orders of magnitude in scan speed provides important information on the effective ion diffusion constant from the peak hysteresis position. The fast‐hysteresis measurements are corroborated by transient charge extraction and capacitance measurements and numerical simulations, which confirm the experimental findings and provide important insights into the charge carrier dynamics. The proposed method to quantify PCE losses due to field screening induced by mobile ions clarifies several important experimental observations and opens up a large range of future experiments. Abstract : Ionic motion is known to impact perovskite solar cells' performance and leads to the appearance of hysteresis in the current–voltage characteristics. However, there is no simple method to quantify their impact on the stabilized performance. Herein, a new method is presented to measure the ion‐free efficiency and determine the loss due to the ions.