Redkin Arkady N, Mitina Alena A, Yakimov Eugene E
Institute of Microelectronics Technology and High-Purity Materials, Russian Academy of Science (IMT RAS), Moscow District, 6 Academician Ossipyan Str., 142432 Chernogolovka, Russia.
Nanomaterials (Basel). 2022 Aug 24;12(17):2922. doi: 10.3390/nano12172922.
Recently, significant progress has been made in the performance of supercapacitors through the development of composite electrodes that combine various charge storage mechanisms. A new method for preparing composite binder-free MnO/MWCNT/Al electrodes for supercapacitors is proposed. The method is based on the original technique of direct growth of layers of multi-walled carbon nanotubes (MWCNTs) on aluminum foil by the catalytic pyrolysis of ethanol vapor. Binder-free MnO/MWCNT/Al electrodes for electrochemical supercapacitors were obtained by simply treating MWCNT/Al samples with an aqueous solution of KMnO under mild conditions. The optimal conditions for the preparation of MnO/MWCNT/Al electrodes were found. The treatment of MWCNT/Al samples in a 1% KMnO aqueous solution for 40 min increased the specific capacitance of the active material of the samples by a factor of 3, up to 100-120 F/g. At the same time, excellent adhesion and electrical contact of the working material to the aluminum substrate were maintained. The properties of the MnO/MWCNT/Al samples were studied by electron probe microanalysis (EPMA), Raman spectroscopy, cyclic voltammetry (CV), and impedance spectroscopy. Excellent charge/discharge characteristics of composite electrodes were demonstrated. The obtained MnO/MWCNT/Al electrodes maintained excellent stability to multiple charge-discharge cycles. After 60,000 CVs, the capacitance loss was less than 20%. Thus, this work opens up new possibilities for using the MWCNT/Al material obtained by direct deposition of carbon nanotubes on aluminum foil for the fabrication of composite binder-free electrodes of supercapacitors.
近年来，通过开发结合了各种电荷存储机制的复合电极，超级电容器的性能取得了显著进展。本文提出了一种制备用于超级电容器的无粘结剂MnO/MWCNT/Al复合电极的新方法。该方法基于通过乙醇蒸汽催化热解在铝箔上直接生长多壁碳纳米管（MWCNT）层的原始技术。通过在温和条件下用KMnO水溶液简单处理MWCNT/Al样品，获得了用于电化学超级电容器的无粘结剂MnO/MWCNT/Al电极。找到了制备MnO/MWCNT/Al电极的最佳条件。在1%的KMnO水溶液中对MWCNT/Al样品处理40分钟，使样品活性材料的比电容提高了3倍，达到100-120F/g。同时，保持了工作材料与铝基板之间的优异附着力和电接触。通过电子探针微分析（EPMA）、拉曼光谱、循环伏安法（CV）和阻抗谱研究了MnO/MWCNT/Al样品的性能。展示了复合电极优异的充放电特性。所获得的MnO/MWCNT/Al电极在多次充放电循环中保持了优异的稳定性。经过60,000次循环伏安后，电容损失小于20%。因此，这项工作为使用通过在铝箔上直接沉积碳纳米管获得的MWCNT/Al材料制造超级电容器的无粘结剂复合电极开辟了新的可能性。
