Journal Article

Dynamic hydrogen-bonding enables high-performance and mechanically robust organic solar cells processed with non-halogenated solvent

Song, Bohao, Wu, Xiangxi, Zhang, Jingyuan, Lu, Guanghao, Ye, Long, Bi, Zhaozhao, Gong, Yufei, Liang, Tongling, Li, Yaowen, Wang, Shijie, Li, Yongfang, Zhou, Kangkang, Ma, Wei, Meng, Lei, Chen, Zekun, Zhang, Ben, He, Haozhe, Li, Xiaojun, Li, Yuechen, Zhuo, Hongmei

2025

Overview

Developing active-layer systems with both high performance and mechanical robustness is a crucial step towards achieving future commercialization of flexible and stretchable organic solar cells (OSCs). Herein, we design and synthesize a series of acceptors BTA-C6, BTA-E3, BTA-E6, and BTA-E9, featuring the side chains of hexyl, and 3, 6, and 9 carbon-chain with ethyl ester end groups respectively. Benefiting from suitable phase separation and vertical phase distribution, the PM6:BTA-E3-based OSCs processed by o -xylene exhibit lower energy loss and improved charge transport characteristic and achieve a power conversion efficiency of 19.92% (certified 19.57%), which stands as the highest recorded value in binary OSCs processed by green solvents. Moreover, due to the additional hydrogen-bonding provided by ethyl ester side chain, the PM6:BTA-E3-based active-layer systems achieve enhanced stretchability and thermal stability. Our work reveals the significance of dynamic hydrogen-bonding in improving the photovoltaic performance, mechanical robustness, and morphological stability of OSCs. Developing high-performance and mechanically robust active-layer systems is crucial to commercializing flexible organic solar cells. Here, authors design small molecule acceptors with ethyl ester side chains and achieve certified efficiency of over 19% for mechanically robust devices.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 639/301/299/946 / 639/4077/909/4101/4096/946 / Charge efficiency / Charge transport / Chemical bonds / Chemistry / Clean energy / Commercialization / Efficiency / Energy / Energy charge / Energy conversion efficiency / Energy loss / Engineering / Ethyl esters / Humanities and Social Sciences / Hydrogen / Hydrogen bonding / Laboratories / Materials science / Molecular structure / Morphology / multidisciplinary / Phase distribution / Phase separation / Photovoltaic cells / Photovoltaics / Polymers / Robustness / Science / Science (multidisciplinary) / Solar cells / Solvents / Stretchability / Thermal stability / Transport properties / Vertical distribution / Vertical separation / Xylene