A Facile Low Prevacuum Treatment to Enhance the Durability of Nonfullerene Organic Solar Cells

Identifier:  imarina:9380952

Handle: https://hdl.handle.net/20.500.11797/imarina9380952

Authors:  Samir, Mohamed; Sacramento, Angel; Almora, Osbel; Pallares, Josep; Marsal, Lluis F; Marsal, Lluis F

Abstract:
Herein, a straightforward vacuum-assisted method is introduced to enhance the stability of nonfullerene organic solar cells (OSCs). The method, termed "prevacuum" involves subjecting the active layer (D18:Y6) to a low-pressure vacuum (-1 bar) before thermal annealing at 100 degrees C. Compared to untreated devices, prevacuum-treated OSCs exhibit a notable increase in power conversion efficiency from 13.71% to 14.90%. This enhancement is attributed to improved light absorption and charge extraction, as evidenced by external quantum efficiency measurements. Moreover, prevacuum treatment significantly improves device stability under operational conditions, with a 30% power loss occurring after 8.25 h compared to 4.5 h for untreated devices. This improvement is attributed to the removal of volatile components and impurities during the vacuum process, leading to a more hydrophobic and stable active layer. The study demonstrates the efficacy of prevacuum treatment as a simple and accessible method for enhancing the performance and longevity of OSCs, paving the way for their broader application in sustainable energy technologies. A vacuum-assisted method, termed "prevacuum," is introduced to improve the stability of nonfullerene organic solar cells. By subjecting the D18:Y6 active layer, deposited on indium tin oxide/hole transport layer (ITO/HTL) to a low-pressure vacuum before thermal annealing, stability improves by removing volatile components and impurities, resulting in a stable active layer, extending the time for 30% power loss.image (c) 2024 WILEY-VCH GmbH