Flexible electrochemical energy storage devices have attracted extensive attention as promising power sources for the ever-growing field of flexible and wearable electronic products. However, the rational design of a novel electrode structure with a good flexibility, high capacity, fast charge-discharge rate and long cycling lifetimes remains a long-standing challenge for developing next-generation flexible energy-storage materials. Herein, we develop a facile and general approach to three-dimensional (3D) interconnected porous nitrogen-doped graphene foam with encapsulated Ge quantum dot/nitrogen-doped graphene yolk-shell nano architecture for high specific reversible capacity (1,220 mAh g^-1), long cycling capability (over 96% reversible capacity retention from the second to 1,000 cycles) and ultra-high rate performance (over 800 mAh g^-1 at 40 C). This work paves a way to develop the 3D interconnected graphene-based high-capacity electrode material systems, particularly those that suffer from huge volume expansion, for the future development of high-performance flexible energy storage systems.

中文翻译：

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具有密封锗/氮掺杂石墨烯卵黄壳纳米结构的3D氮掺杂石墨烯泡沫，用于高性能柔性锂离子电池。

柔性电化学储能装置作为柔性和可穿戴电子产品不断发展的领域中有希望的电源已引起了广泛的关注。然而，合理设计具有良好的柔性，高容量，快速的充放电速率和长的循环寿命的新型电极结构仍然是开发下一代柔性储能材料的长期挑战。本文中，我们开发了一种简便且通用的方法，用于具有高比可逆容量（1,220 mAh g ^-1）的具有互连的Ge量子点/氮掺杂石墨烯卵黄壳纳米结构的三维（3D）互连多孔氮掺杂石墨烯泡沫），长循环能力（从第二个循环到1,000个循环，可逆容量保持率超过96％）和超高倍率性能（在40 C下超过800 mAh g ^-1）。这项工作为开发3D互连的基于石墨烯的高容量电极材料系统，特别是那些遭受巨大体积膨胀的材料系统，为高性能柔性储能系统的未来发展铺平了道路。