A general approach toward flexible supercapacitor electrode based on metal hydroxide is developed, which offers ultrahigh areal capacitance without compromising their gravimetric capacitance and mechanical properties. As a prototype, bendable freestanding film is fabricated by coating graphene (RGO)-wrapped flowery Ni(OH)₂ on bacterial cellulose (BC) with a rational combination of hydrothermal method and filtration technology. This as-assembled hierarchically structured flexible electrode is characterized by remarkable areal capacitance of 10.44 F cm⁻² (877.1 F g⁻¹) at a large mass loading of 11.9 mg cm⁻², excellent cycling stability with 93.6% capacitance retention after 15,000 cycles, high flexibility including bending to arbitrary angles (even 180°) and prominent tensile strength (48.8 MPa at wet state). Furthermore, it is hoped that the typical method can be applied for realizing other metal oxide/hydroxide flexible electrodes. The simple, high scalable, low-cost, and general strategy could open up new opportunities for flexible energy storage devices.

中文翻译：

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Ni（OH）2 /石墨烯/细菌纤维素纸的简便合成，可用于大面积的质量，机械韧性和柔性的超级电容器电极

开发了一种基于金属氢氧化物的柔性超级电容器电极的通用方法，该方法可提供超高的面电容，而不会损害其重量电容和机械性能。作为原型，可弯曲的独立膜是通过将石墨烯（RGO）包裹的花朵状Ni（OH）₂涂覆在细菌纤维素（BC）上并结合水热方法和过滤技术而制成的。这种组装的分层结构的柔性电极的特征在于，在11.9 mg cm ^-2的大质量载荷下，其出色的面积电容为10.44 F cm ^-2（877.1 F g ^-1）。，出色的循环稳定性，在15,000次循环后具有93.6％的电容保持力，高柔韧性包括弯曲至任意角度（甚至180°）和出色的拉伸强度（湿态下为48.8 MPa）。此外，希望可以将典型方法应用于实现其他金属氧化物/氢氧化物柔性电极。简单，高度可扩展，低成本和通用的策略可以为灵活的储能设备开辟新的机会。