Sico Giuliano, Montanino Maria, Loffredo Fausta, Borriello Carmela, Miscioscia Riccardo
Portici Research Centre, ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, 80055 Portici, Italy.
Materials (Basel). 2024 Dec 25;18(1):22. doi: 10.3390/ma18010022.
Polyvinylidene fluoride (PVDF)-based materials are the most researched polymers in the field of energy harvesting. Their production in thin-film form through printing technologies can potentially offer several manufacturing and performance advantages, such as low-cost, low-temperature processing, use of flexible substrates, custom design, low thermal inertia and surface-scaling performance. However, solution-based processes, like printing, miss fine control of the microstructure during film-forming, making it difficult to achieve a high level of polarization, necessary for PVDF to exhibit electroactive characteristics. Here, corona treatment is investigated for the poling of gravure-printed polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) films, as a particularly suitable poling method for printing since it is rapid, contactless and scalable, and no metal electrodes are required. Effects of corona conditioning on the functional properties of the printed films were examined and discussed. Electroactive properties of corona-poled printed films improved manyfold when they were treated at 9 kV, near room temperature (30 °C) and using very short treatment time (30 s). In particular, piezoelectric and pyroelectric coefficients improved tenfold and by two orders of magnitude, respectively. Considering the upscaling potential of roll-to-roll gravure printing and corona poling, combined with the area-scaling performance of thin-film-based generators, our results can enable the corona-printing process for mass production of future electroactive flexible PVDF-based devices.
聚偏二氟乙烯（PVDF）基材料是能量收集领域中研究最多的聚合物。通过印刷技术将其制成薄膜形式，可能会带来一些制造和性能方面的优势，如低成本、低温加工、可使用柔性基板、定制设计、低热惯性和表面缩放性能。然而，像印刷这样基于溶液的工艺在成膜过程中对微观结构缺乏精细控制，使得难以实现PVDF呈现电活性特性所需的高极化水平。在此，研究了电晕处理用于凹版印刷的聚偏二氟乙烯 - 三氟乙烯（PVDF-TrFE）薄膜的极化，这是一种特别适合印刷的极化方法，因为它快速、非接触且可扩展，并且不需要金属电极。研究并讨论了电晕处理对印刷薄膜功能特性的影响。当在接近室温（30°C）下以9 kV进行处理且处理时间非常短（30秒）时，电晕极化印刷薄膜的电活性特性提高了许多倍。特别是，压电系数和热电系数分别提高了十倍和两个数量级。考虑到卷对卷凹版印刷和电晕极化的扩大生产潜力，再结合基于薄膜的发电机的面积缩放性能，我们的研究结果能够实现电晕印刷工艺，用于大规模生产未来基于PVDF的电活性柔性器件。
