A novel naphthalene diimide-based conjugated polymer as an electron transport material for non-fullerene organic solar cells

• Published in: New journal of chemistry Vol. 46; no. 22; pp. 1611 - 1617
• Main Authors: Gong, Shuai, Yin, Zhipeng, Zhang, Xinxin, He, Xiang, Zhang, Wenjun, Yang, Shangfeng, Song, Weijie
• Format: Journal Article
• Language: English
• Published: CAMBRIDGE Royal Soc Chemistry 06.06.2022; Royal Society of Chemistry
• Subjects: Aliphatic compounds; Chemistry; Chemistry, Multidisciplinary; Diimide; Electron transport; Energy conversion efficiency; Fullerenes; Inert atmospheres; Naphthalene; Open circuit voltage; Photovoltaic cells; Physical Sciences; Polymers; Science & Technology; Silver; Solar cells; Work functions; ACCEPTORS; DONOR; EFFICIENT
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d2nj00895e

Electron transport materials (ETMs) play an important role in organic solar cells (OSCs) and the rapidly evolving non-fullerene acceptors have higher demands for ETMs. A novel naphthalene diimide-based conjugated polymer (PNDI-NN) with aliphatic amino side chains at the N-position of naphthalene diimide was synthesized and introduced as an ETM in non-fullerene OSCs. The only N-substituted aliphatic amino side chains endow PNDI-NN with good solubility in alcohol and an intense self-doping effect, which can not only reduce the work function of the metal electrode (Ag), but also have a good coverage on the active layer and promote electron transport. The device with PNDI-NN showed the best power conversion efficiency of 15.6% with an improved open-circuit voltage ( V OC ) and fill factor (FF). The device also exhibited good long-term stability in an inert atmosphere, in a humid environment and under continuous heating. The only aliphatic amino side chains at the N-position of naphthalene diimide endow novel electron transport materials with good film-forming and interface modification properties, which improves the device efficiency and stability.