Ge Zhongwei, Qiao Jiawei, Li Yun, Song Jiali, Duan Xiaopeng, Fu Zhen, Hu Haixia, Yang Renqiang, Yin Hang, Hao Xiaotao, Sun Yanming
School of Chemistry, Beihang University, 100191, Beijing, P. R. China.
School of Physics State Key Laboratory of Crystal Materials, Shandong University, 250100, Jinan, P. R. China.
Angew Chem Int Ed Engl. 2025 Jan 2;64(1):e202413309. doi: 10.1002/anie.202413309. Epub 2024 Oct 25.
Strong electron-phonon coupling can hinder exciton transport and induce undesirable non-radiative recombination, resulting in a shortened exciton diffusion distance and constrained exciton dissociation in organic solar cells (OSCs). Therefore, suppressing electron-phonon coupling is crucially important for achieveing high-performance OSCs. Here, we employ the solid additive to regulating electron-phonon coupling in OSCs. The planar configuration of SA1 confers a significant advantage in suppressing lattice vibrations in the active layers, reducing the scattering of excitons by phonons. Consequently, a slow but sustained hole transfer process is identified in the SA1-assisted film, indicating an enhancement in hole transfer efficiency. Prolonged exciton diffusion length and exciton lifetime are achieved in the blend film processed with SA1, attributed to a low non-radiative recombination rate and low energetic disorder for charge carrier transport. As a result, a high efficiency of 20 % was achieved for ternary device with a remarkable short-circuit current. This work highlights the important role of suppressing electron-phonon coupling in improving the photovoltaic performance of OSCs.
强电子-声子耦合会阻碍激子传输并引发不良的非辐射复合，导致有机太阳能电池（OSCs）中激子扩散距离缩短以及激子解离受限。因此，抑制电子-声子耦合对于实现高性能有机太阳能电池至关重要。在此，我们采用固体添加剂来调控有机太阳能电池中的电子-声子耦合。SA1的平面构型在抑制有源层中的晶格振动方面具有显著优势，减少了声子对激子的散射。因此，在SA1辅助的薄膜中发现了一个缓慢但持续的空穴转移过程，这表明空穴转移效率有所提高。在用SA1处理的共混薄膜中实现了更长的激子扩散长度和激子寿命，这归因于较低的非辐射复合率以及电荷载流子传输的低能量无序性。结果，具有显著短路电流的三元器件实现了20%的高效率。这项工作突出了抑制电子-声子耦合在提高有机太阳能电池光伏性能方面的重要作用。
