Current collector is an important component of supercapacitors to transport electrons from/to the electroactive materials. However, its role has not received the attention it deserves. In this work, we have put forward a facile electrochemical approach that treats graphite (GP) to obtain superficial expansion-treated graphite (Ex-GP), which is used as the current collector/substrate for electrodeposition of poly(3,4-ethylenedioxythiophene) (PEDOT). We have also examined and optimized the electrodeposition mode and parameter of PEDOT. Electrochemical measurements indicate that Ex-GP/PEDOT electrodes exhibit obviously enhanced electrochemical performances comparing to GP/PEDOT electrodes. This is attributed to the reduced constriction and spreading resistance for the former, due to increased area of contact spots at the current collector/electroactive material interface. Herein Ex-GP/PEDOT electrodes achieve a high specific capacitance of 135.4 mF cm⁻² at 0.5 mA cm⁻². A highly flexible solid-state supercapacitor is further fabricated with Ex-GP/PEDOT electrodes. The supercapacitor device exhibits high rate capability (maintaining 73.8% of capacitance as current density increases for 20 times), superior energy/power characteristics (1.45 mW h cm⁻³ at power density of 49.6 mW cm⁻³), and remarkable cycle performance (maintaining 95.8% of initial capacitance after 5000 cycles), which holds great promise for use in flexible electronics. The present study is expected to stimulate further research activities on optimizing current collector/active material interface for boosted supercapacitive properties.

集电器是超级电容器的重要组成部分，超级电容器用于将电子从电活性材料中传输到电子活性材料中。但是，它的作用并未得到应有的重视。在这项工作中，我们提出了一种处理石墨（GP）以获得表面膨胀处理过的石墨（Ex-GP）的简便电化学方法，该方法可用作电沉积聚（3,4-乙撑二氧噻吩）的集流体/基材）（PEDOT）。我们还检查并优化了PEDOT的电沉积模式和参数。电化学测量表明，与GP / PEDOT电极相比，Ex-GP / PEDOT电极表现出明显增强的电化学性能。这归因于前者的收缩和扩张阻力降低，由于集电器/电活性材料界面处的接触点面积增加。本文中的Ex-GP / PEDOT电极可实现135.4 mF cm的高比电容^-2 在0.5毫安厘米^-2。用Ex-GP / PEDOT电极进一步制造了高度灵活的固态超级电容器。的超级电容器装置具有高倍率性能（保持电容的73.8％，作为20倍的电流密度增大），优异的能量/功率特性（1.45毫瓦高厘米^-3  49.6毫瓦厘米的功率密度^-3），和显着的循环性能（在5000次循环后仍可保持95.8％的初始电容），这在柔性电子产品中具有广阔的前景。预期本研究将激发进一步的研究活动，以优化集流体/活性材料界面以增强超级电容性能。