Lin Baoying, Zheng Yinyin, Wang Jinglu, Tu Qian, Tang Wentao, Chen Liangzhe
School of Electronic Information Engineering, Jingchu University of Technology, Jingmen 448000, China.
Nanomaterials (Basel). 2023 Aug 8;13(16):2282. doi: 10.3390/nano13162282.
The emergence of the Internet of things stimulates the pursuit of flexible and miniaturized supercapacitors. As an advanced technology, screen printing displays vigor and tremendous potential in fabricating supercapacitors, but the adoption of high-performance ink is a great challenge. Here, hierarchical VO with rodlike texture was prepared via a facile template-solvothermal route; and the morphology, component, and valence bond information are characterized meticulously. Then, the screen-printed inks composed of VO, acetylene black, and PVDF are formulated, and the rheological behaviors are studied detailedly. Benefitting from the orderly aligned ink, the optimal screen-printed electrode can exhibit an excellent specific capacitance of 274.5 F/g at 0.3 A/g and capacitance retention of 81.9% after 5000 cycles. In addition, a flexible VO symmetrical supercapacitor (SSC) is screen-printed and assembled on the Ag current collector, exhibiting a decent areal specific capacitance of 322.5 mF/cm at 0.5 mA/cm, outstanding cycling stability of 90.8% even after 5000 cycles, satisfactory maximum energy density of 129.45 μWh/cm at a power density of 0.42 mW/cm, and remarkable flexibility and durability. Furthermore, a single SSC enables the showing of an actual voltage of 1.70 V after charging, and no obvious self-discharge phenomenon is found, revealing the great applied value in supply power. Therefore, this work provides a facile and low-cost reference of screen-printed ink for large-scale fabrication of flexible supercapacitors.
物联网的出现激发了对柔性和小型化超级电容器的追求。作为一项先进技术，丝网印刷在制造超级电容器方面展现出活力和巨大潜力，但采用高性能墨水是一项巨大挑战。在此，通过简便的模板溶剂热法制备了具有棒状结构的分级VO；并对其形态、成分和价键信息进行了细致表征。然后，配制了由VO、乙炔黑和PVDF组成的丝网印刷墨水，并详细研究了其流变行为。受益于有序排列的墨水，最优的丝网印刷电极在0.3 A/g时可表现出274.5 F/g的优异比电容，5000次循环后电容保持率为81.9%。此外，在Ag集流体上丝网印刷并组装了柔性VO对称超级电容器（SSC），在0.5 mA/cm时表现出322.5 mF/cm的体面面积比电容，即使在5000次循环后仍具有90.8%的出色循环稳定性，在0.42 mW/cm的功率密度下具有129.45 μWh/cm的令人满意的最大能量密度，以及卓越的柔韧性和耐久性。此外，单个SSC在充电后可显示1.70 V的实际电压，且未发现明显的自放电现象，揭示了其在供电方面的巨大应用价值。因此，这项工作为大规模制造柔性超级电容器提供了一种简便且低成本的丝网印刷墨水参考。
