Ge Yansong, Hu Lin, Zhang Lifu, Fu Qingxia, Xu Guodong, Xing Zhi, Huang Liqiang, Zhou Weihua, Chen Yiwang
School of Material Science and Engineering, Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China.
Institute of Polymers and Energy Chemistry (IPEC), Nanchang University, 999 Xuefu Avenue, Nanchang 330031, China.
ACS Appl Mater Interfaces. 2020 Mar 4;12(9):10706-10716. doi: 10.1021/acsami.9b18095. Epub 2020 Feb 24.
Despite the breakthroughs in power conversion efficiency (PCE) values of organic solar cells (OSCs), the other important issue concerns stability, which is urgently needed to be resolved for potential commercialization. A commercial and chemically stable polyolefin elastomer (POE) was incorporated into high-performance PBDB-T:ITIC, PM6:IT-4F, and PM6:Y6 nonfullerene systems to serve as the anode interfacial layer, affording remarkably improved mechanical and air stabilities when compared with those of the most studied MoO interfacial layer. The POE was found to selectively transport holes rather than electrons due to the upshifted surface contact potential of the active layer and the better ohmic contact between the active layer and the electrode. The POE serving as an encapsulating layer is supposed to suppress the penetration of water and oxygen in addition to the diffusion of Ag atoms into the active layer. After storing in an air environment with a humidity of approximately 70% for 150 days, the PCE of the device based on PM6:IT-4F with the POE anode interfacial layer decreased from 11.88 to 9.60%, retaining 80.8% of its original PCE value. The device using MoO as the anode interfacial layer showed a PCE value that was sharply reduced from 12.31 to 2.98% after storing for only 30 days. The POE could be potentially useful for flexible and large-scale device fabrication, accelerating the commercialization of OSCs.
尽管有机太阳能电池（OSC）的功率转换效率（PCE）值取得了突破，但另一个重要问题是稳定性，这是潜在商业化迫切需要解决的问题。将一种商业上可用且化学稳定的聚烯烃弹性体（POE）引入高性能的PBDB-T:ITIC、PM6:IT-4F和PM6:Y6非富勒烯体系中作为阳极界面层，与研究最多的MoO界面层相比，其机械稳定性和空气稳定性都有显著提高。由于活性层表面接触电位的上移以及活性层与电极之间更好的欧姆接触，发现POE能够选择性地传输空穴而非电子。用作封装层的POE除了能抑制Ag原子扩散到活性层外，还应能抑制水和氧气的渗透。在湿度约为70%的空气环境中储存150天后，基于带有POE阳极界面层的PM6:IT-4F的器件的PCE从11.88%降至9.60%，保留了其原始PCE值的80.8%。使用MoO作为阳极界面层的器件在仅储存30天后，其PCE值从12.31%急剧降至2.98%。POE可能对柔性和大规模器件制造有用，从而加速OSC的商业化。
