Pan Hailin, Wang Jie, Chen Zhi, Su Ziqi, Tang Zheng, Ma Zaifei
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Center for Advanced Low-Dimension Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China.
ACS Appl Mater Interfaces. 2023 Aug 23;15(33):39677-39688. doi: 10.1021/acsami.3c08040. Epub 2023 Aug 12.
Developing transparent conductors to replace indium tin oxide (ITO) is a critical objective in the field of organic optoelectronics. Non-atomically doped (NAD) ZnO thin films, while currently exhibiting limited conductivity, are highly promising candidates due to their unique advantages, such as having complete transparency in both the visible and near-infrared spectral regions, solution processability, and the desired surface electronic properties. In this work, the impact of surface modification by insulating polymers on the ultraviolet-enhanced conductivity of NAD-ZnO films is investigated. It was found that polymer modifiers that are rich in amino and hydroxyl groups are effective at increasing the concentration of oxygen vacancies and the conductivity of NAD-ZnO films. The highest conductivity of over 1000 S cm, which is more than twice as high as the previous record for NAD-ZnO films, is achieved using polyethylenimine ethoxylated (PEIE) to modify NAD-ZnO films. Subsequently, the replacement of ITO in organic photovoltaic devices by a ZnO/PEIE electrode is realized. The ZnO/PEIE-based OPV devices that were created exhibit performances comparable to those of ITO-based devices under simulated solar illumination and performances better than those achieved with ITO-based devices under simulated indoor illumination. These results make NAD-ZnO a promising candidate for the widespread replacement of ITO in optoelectronic devices.
开发透明导体以替代氧化铟锡（ITO）是有机光电子领域的一个关键目标。非原子掺杂（NAD）的ZnO薄膜虽然目前导电性有限，但因其独特优势，如在可见光和近红外光谱区域具有完全透明性、可溶液加工性以及所需的表面电子特性，而成为极具潜力的候选材料。在这项工作中，研究了绝缘聚合物表面改性对NAD-ZnO薄膜紫外增强导电性的影响。发现富含氨基和羟基的聚合物改性剂能有效增加NAD-ZnO薄膜的氧空位浓度和导电性。使用乙氧基化聚乙烯亚胺（PEIE）改性NAD-ZnO薄膜，实现了超过1000 S/cm的最高电导率，这比NAD-ZnO薄膜的先前记录高出两倍多。随后，实现了用ZnO/PEIE电极替代有机光伏器件中的ITO。所制备的基于ZnO/PEIE的有机光伏器件在模拟太阳光照下表现出与基于ITO的器件相当的性能，在模拟室内光照下表现优于基于ITO的器件。这些结果使NAD-ZnO成为在光电器件中广泛替代ITO的有前途的候选材料。
