Yeom Hye Rim, Heo Jungwoo, Kim Gi-Hwan, Ko Seo-Jin, Song Seyeong, Jo Yimhyun, Kim Dong Suk, Walker Bright, Kim Jin Young
School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 698-798, South Korea.
Phys Chem Chem Phys. 2015 Jan 21;17(3):2152-9. doi: 10.1039/c4cp04788e. Epub 2014 Dec 8.
Although polymer solar cells (PSCs) have received a tremendous amount of attention in recent years, a number of criteria must be met in order for them to be suitable as practical and commercially feasible power sources, including high performance, good air stability and inexpensive manufacturing. In this contribution, we determine the optimal top electrode for practical PSC fabrication by investigating the influence of the electrode material on the optical properties and performance of PSC devices. The optical properties of eight metals were considered, out of which three metal electrodes (aluminum (Al), silver (Ag), gold (Au)) with the best optical properties were used to prepare inverted PSC devices comprising a blended polymer thieno[3,4-b]thiophene/benzodithiophene (PTB7) and [6,6]-phenyl C71-butyric acid methyl ester (PC71BM). Among the photovoltaic parameters, the short circuit current density (JSC) was most strongly affected by the optical properties of the top electrode. In the results of the experiment, the J(SC) of the Al and Ag electrode devices was found to be approximately 13% (13.4 → 15.1 mA cm(-2)) higher than the Au electrode device due to the significant parasitic absorption of light by Au at wavelengths below 600 nm. In contrast, Al and Ag electrodes have high reflectance throughout the visible spectrum, which leads to high J(SC). Ag electrodes have relatively good stability to ambient exposure, maintaining over 96% of the original efficiency after 170 hours; this stability is comparable to Au. These data lead to the conclusion that Ag is the optimal top electrode material for use in inverted devices.
尽管近年来聚合物太阳能电池（PSC）受到了极大关注，但要使其成为实用且具有商业可行性的电源，必须满足若干标准，包括高性能、良好的空气稳定性以及低成本制造。在本论文中，我们通过研究电极材料对PSC器件光学性质和性能的影响，确定了用于实际PSC制造的最佳顶部电极。考虑了八种金属的光学性质，其中具有最佳光学性质的三种金属电极（铝（Al）、银（Ag）、金（Au））被用于制备由聚合物噻吩并[3,4 - b]噻吩/苯并二噻吩（PTB7）和[6,6] - 苯基C71 - 丁酸甲酯（PC71BM）混合而成的倒置PSC器件。在光伏参数中，短路电流密度（JSC）受顶部电极光学性质的影响最为强烈。在实验结果中，由于金在波长低于600 nm时对光有显著的寄生吸收，铝和银电极器件的J(SC)比金电极器件高出约13%（13.4 → 15.1 mA cm(-2)）。相比之下，铝和银电极在整个可见光谱范围内具有高反射率，这导致了高J(SC)。银电极对环境暴露具有相对较好的稳定性，在170小时后仍保持超过96%的原始效率；这种稳定性与金相当。这些数据得出结论，银是用于倒置器件的最佳顶部电极材料。
