The choice of electrode materials affects the electrochemical performance of supercapacitors, and the selection of suitable electrode materials is necessary to enable the industrialization of supercapacitors. The conductive polymer polypyrrole is well known to researchers for its excellent electrochemical properties, but pure polypyrrole does not fulfill its advantages. The disadvantage is that the microstructure of the polypyrrole molecules, which is favorable for energy storage when supercapacitors are being charged and discharged, is greatly damaged by the contraction/expansion of the polypyrrole molecular chains, which directly affects the electrochemical performance of the supercapacitors assembled subsequently. So firstly, we modified PPy by using the functional group nature of 3-amino-4-methylene-phenylboronic acid (g-PPy) to give it more active sites. Secondly, MXene acts as the backbone of g-PPy, which limits the expansion and contraction of the volume supercapacitors and improves cycle stability when charging and discharging. In contrast, the compounded MXene/g-PPy has good specific capacitance and stability after several thousand cycles, due to the nature of the functional group of 3-amino-4-methylenebenzeneboronic acid, a large number of g-PPy active sites, the good hydrophilicity of the MXene surface for interaction with sodium dodecylbenzene sulfonate and the hydrogen bonding between MXene and g-PPy, Even after 10000 charge/discharge cycles, its stability is significantly improved with a capacity retention rate of 98.6 %. In addition, the corresponding symmetrical supercapacitors were tested to exhibit significant cycling stability at a low temperature. This study, therefore, provides a method for the preparation of MXene based electrodes with high cycling stability by modifying the electrodes.

中文翻译：

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基于MXene/球形g-PPy复合电极的高稳定性超级电容器

电极材料的选择影响超级电容器的电化学性能，选择合适的电极材料对于实现超级电容器的产业化至关重要。导电聚合物聚吡咯以其优异的电化学性能而为研究人员所熟知，但纯聚吡咯并不能发挥其优点。缺点是，超级电容器充放电时有利于储能的聚吡咯分子微观结构因聚吡咯分子链的收缩/膨胀而受到极大破坏，直接影响后续组装的超级电容器的电化学性能。 。因此，我们首先利用3-氨基-4-亚甲基-苯基硼酸（g-PPy）的官能团性质对PPy进行修饰，赋予其更多的活性位点。其次，MXene作为g-PPy的主干，限制了超级电容器体积的膨胀和收缩，提高了充放电时的循环稳定性。相比之下，复合的MXene/g-PPy由于3-氨基-4-亚甲基苯硼酸官能团的性质，大量的g-PPy活性位点，在数千次循环后具有良好的比电容和稳定性。 MXene表面良好的亲水性，与十二烷基苯磺酸钠的相互作用以及MXene与g-PPy之间的氢键作用，即使在10000次充放电循环后，其稳定性也显着提高，容量保持率高达98.6%。此外，相应的对称超级电容器经过测试，在低温下表现出显着的循环稳定性。因此，本研究提供了一种通过对电极进行修饰来制备具有高循环稳定性的MXene基电极的方法。