LAUSR

Micro-supercapacitors (MSCs) have emerged as one competitive candidate of high-performance, flexible, safe, portable and wearable energy storage devices. However, improving their electrochemical performance from electrode materials to assembled devices still remains huge challenges. Here, we for the first time synthesized two-dimensional (2D), ultrathin, mesoporous polypyrrole-based graphene nanosheets uniformly anchored with redox polyoxometalate (mPPy@rGO-POM) by soft template approach. Further, using a layer-by-layer deposition and mask-assisted technique, the compactly stacked and sandwich-like hybrid film (mPGM) based on pseudocapacitive mPPy@rGO-POM nanosheets and electrochemically exfoliated graphene was directly fabricated as binder- and additive-free interdigital electrodes for all-solid- state planar micro-supercapacitors (mPGM-MSCs). Notably, the resulted mPGM-MSCs exhibited outstanding areal capacitance (115 mF cm–2), remarkably enhanced volumetric capacitance (137 F cm–3 at 1 mV s–1) in comparison with MSCs based on the films of mPPy@rGO without POM anchoring (95 F cm–3), and non-porous polypyrrole-graphene (68 F cm–3). Further, mPGM-MSCs disclosed robust mechanical flexibility with ~96% of capacitance retention at a highly bending angle of 180°, and impressive parallel or serial interconnection for boosting capacitance or voltage output. As a consequence, our proposed strategy of filling the redox species into mesoporous graphene and other 2D nanosheets will open up new ways to manufacture high-compact and flexible energy storage devices ranging from supercapacitors to batteries.摘要微型超级电容器是一种新型的、柔性化、易集成、可穿戴便携的电化学储能器件, 但提高电极材料和器件的性能仍面临着巨大的 挑战. 本文成功首次制备出一种二维磷钼酸复合介孔聚吡咯/石墨烯纳米片, 具有超薄、比表面积大、孔道结构发达、导电性好、赝电容 高的特点. 然后, 在十指交叉形状的掩模版协助下, 采用交替沉积的方法, 一步制备出电化学剥离石墨烯和磷钼酸复合介孔聚吡咯/石墨烯 纳米片三明治层状结构、高致密、高导电的复合薄膜图案化电极. 该复合薄膜图案化电极应用于全固态平面微型电容器, 表现出显著提 高的面电容(115 mF cm–2)和体电容(137 F cm–3), 以及优异的机械柔性和可串/并联直接集成的特征. 总之, 本文通过对石墨烯基二维材料 的合理设计和微型超级电容器的高效组装实现了器件性能的极大提高, 为发展新一代的微型储能器件提供了一定的科学依据.