Li Youzhan, Wu Jiang, Tang Hao, Yi Xueting, Liu Zekun, Yang Qingqing, Fu Yingying, Liu Jian, Xie Zhiyuan
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, P. R. China.
ACS Appl Mater Interfaces. 2022 Jul 13;14(27):31054-31065. doi: 10.1021/acsami.2c05504. Epub 2022 Jun 28.
The power conversion efficiency (PCE) of halogenated solvent spin-coated organic solar cells (OSCs) has been boosted to a high level (>18%) by developing efficient photovoltaic materials and precise morphological control. However, the PCE of OSCs prepared from non-halogenated solvents and with a scalable printing process is far behind, limited by tough morphology manipulation. Herein, we have fabricated ternary OSCs by using layer-by-layer (LBL) blade-coating and a non-halogenated solvent. The ternary OSCs based on the PM6:IT-M(1:0.2)/BTP-eC9 active layer are processed with the hydrocarbon solvent 1,2,4-trimethylbenzene with no need of any additives and post-treatment. The vertical donor/acceptor distribution is optimized by LBL blade-coating within the PM6:IT-M(1:0.2)/BTP-eC9 active layer. The cascade acceptor IT-M blended in PM6 not only attenuates the damage of BTP-eC9 to the PM6 crystallization, leading to a dense nanofiber-like morphology, but also prefers to reside between PM6 and BTP-eC9 to form a cascade energy level alignment for a fast charge-transfer process. Finally, the improved morphology and crystallization lead to a reduced molecular recombination, low energy loss, and high open-circuit voltage. The prepared non-halogenated solvent and LBL blade-coated OSCs achieve a PCE of 17.16%. The work provides an approach to fabricate hydrocarbon solvent-processed high-performance OSCs by employing LBL blade-coating and a ternary strategy.
通过开发高效的光伏材料和精确的形貌控制，卤化溶剂旋涂有机太阳能电池（OSC）的功率转换效率（PCE）已提高到较高水平（>18%）。然而，由非卤化溶剂制备且采用可扩展印刷工艺的OSC的PCE远远落后，这受到严格的形貌操控限制。在此，我们通过逐层（LBL）刮涂和非卤化溶剂制备了三元OSC。基于PM6:IT-M(1:0.2)/BTP-eC9活性层的三元OSC采用烃类溶剂1,2,4-三甲基苯进行处理，无需任何添加剂和后处理。通过在PM6:IT-M(1:0.2)/BTP-eC9活性层内进行LBL刮涂优化垂直供体/受体分布。混入PM6中的级联受体IT-M不仅减弱了BTP-eC9对PM6结晶的破坏，形成致密的纳米纤维状形貌，而且更倾向于位于PM6和BTP-eC9之间，形成级联能级排列以实现快速电荷转移过程。最后，改善的形貌和结晶导致分子复合减少、能量损失降低以及开路电压升高。所制备的非卤化溶剂和LBL刮涂的OSC实现了17.16%的PCE。这项工作提供了一种通过采用LBL刮涂和三元策略来制备烃类溶剂处理的高性能OSC的方法。
