Yang Panpan, Sun Chao, Fu Xifeng, Cheng Shuo, Chen Jingfu, Zhang Hui, Nan Zi-Ang, Yang Jinxin, Zhao Xin-Jing, Xie Li-Qiang, Meng Lingyi, Tian Chengbo, Wei Zhanhua
Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing, Institute of Luminescent Materials and Information Displays, College of Materials Science and Engineering, Huaqiao University, Xiamen 361021, China.
CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China.
J Am Chem Soc. 2024 Jan 31;146(4):2494-2502. doi: 10.1021/jacs.3c10515. Epub 2023 Dec 21.
Designing and synthesizing fullerene bisadducts with a higher-lying conduction band minimum is promising to further improve the device performance of tin-based perovskite solar cells (TPSCs). However, the commonly obtained fullerene bisadduct products are isomeric mixtures and require complicated separation. Moreover, the isomeric mixtures are prone to resulting in energy alignment disorders, interfacial charge loss, and limited device performance improvement. Herein, we synthesized single-isomer C- and C-based diethylmalonate functionalized bisadducts (CBB and CBB) by utilizing the steric-hindrance-assisted strategy and determined all molecular structures involved by single crystal diffraction. Meanwhile, we found that the different solvents used for processing the fullerene bisadducts can effectively regulate the molecular packing in their films. The dense and amorphous fullerene bisadduct films prepared by using anisole exhibited the highest electron mobility. Finally, CBB- and CBB-based TPSCs showed impressive efficiencies up to 14.51 and 14.28%, respectively. These devices also exhibited excellent long-term stability. This work highlights the importance of developing strategies to synthesize single-isomer fullerene bisadducts and regulate their molecular packing to improve TPSCs' performance.
设计并合成具有更高导带最小值的富勒烯双加合物有望进一步提升锡基钙钛矿太阳能电池（TPSCs）的器件性能。然而，常见的富勒烯双加合物产物是异构体混合物，需要复杂的分离过程。此外，异构体混合物容易导致能量排列紊乱、界面电荷损失以及器件性能提升受限。在此，我们利用空间位阻辅助策略合成了单异构体的基于C和C的丙二酸二乙酯官能化双加合物（CBB和CBB），并通过单晶衍射确定了所有相关分子结构。同时，我们发现用于处理富勒烯双加合物的不同溶剂能够有效调节其薄膜中的分子堆积。使用苯甲醚制备的致密非晶态富勒烯双加合物薄膜展现出最高的电子迁移率。最后，基于CBB和CBB的TPSCs分别展现出高达14.51%和14.28%的令人印象深刻的效率。这些器件还表现出优异的长期稳定性。这项工作突出了开发合成单异构体富勒烯双加合物并调节其分子堆积以改善TPSCs性能策略的重要性。
