Flexible supercapacitor electrodes with high mass loading are crucial for obtaining favorable electrochemical performance but still challenging due to sluggish electron and ion transport. Herein, rationally designed CNT/MnO₂/graphene-grafted carbon cloth electrodes are prepared by a “graft-deposit-coat” strategy. Due to the large surface area and good conductivity, graphene grafted on carbon cloth offers additional surface areas for the uniform deposition of MnO₂ (9.1 mg cm⁻²) and facilitates charge transfer. Meanwhile, the nanostructured MnO₂ provides abundant electroactive sites and short ion transport distance, and CNT coated on MnO₂ acts as interconnected conductive “highways” to accelerate the electron transport, significantly improving redox reaction kinetics. Benefiting from high mass loading of electroactive materials, favorable conductivity, and a porous structure, the electrode achieves large areal capacitances without compromising rate capability. The assembled asymmetric supercapacitor demonstrates a wide working voltage (2.2 V) and high energy density of 10.18 mWh cm⁻³.

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具有高质量负载的柔性超级电容器电极对于获得良好的电化学性能至关重要，但由于电子和离子传输缓慢，仍然具有挑战性。在此，通过“接枝沉积涂层”策略制备合理设计的CNT / MnO ₂ /石墨烯接枝的碳布电极。由于较大的表面积和良好的导电性，接枝在碳布上的石墨烯为MnO ₂（9.1 mg cm ^-2）的均匀沉积提供了额外的表面积，并促进了电荷转移。同时，纳米结构的MnO ₂提供了丰富的电活性位点和短的离子迁移距离，并且CNT被包覆在MnO _2上充当互连的导电“高速公路”，以加速电子传输，从而显着改善氧化还原反应动力学。得益于高质量的电活性材料负载，良好的导电性和多孔结构，该电极可在不影响倍率性能的情况下实现较大的面电容。组装的非对称超级电容器显示出较宽的工作电压（2.2 V）和10.18 mWh cm ^-3的高能量密度。

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