Abstract：
Scalable production of reduced graphene oxide (rGO) films with high mechanical-electrical properties is desirable as these films are candidates for wearable electronics devices and energy storage applications. Removing structural incompleteness such as wrinkles or voids in the graphene films, which are generated from the assembly process, would greatly optimize their mechanical properties. However, the densely stacked graphene sheets in the films degrade their ionic kinetics and thus limit their development. Here, a horizontal-longitudinal-structure modulating strategy is demonstrated to produce enhanced mechanical, conductive, and capacitive graphene films. Typically, two-dimensional large graphene sheets (LGS) induce regular stacking of graphene oxide (GO) during the assembly process to reduce wrinkles, while one-dimensional single-walled carbon nanotubes (SWCNT) bridge with graphene sheets to strengthen the multidirectional intercalation and reduce GO layer restacking. The simultaneous incorporation of LGS and SWCNT synergistically creates a fine microstructure by improving the alignment of graphene sheets, increasing continuous conductive pathways to facilitate electron transport, and enlarging interlayer spacing to promote electrolyte ion diffusion. As a result, the obtained graphene films are flat and exhibit signally reinforced mechanical properties, electrical conductivity (38727 S m-1), as well as specific capacitance (232 F g-1) as supercapacitor electrodes compared to those of original rGO films. Moreover, owing to the comprehensive improved properties, a flexible gel supercapacitor assembled by the graphene film-based electrodes shows high energy density, good flexibility, and excellent cycling stability (93.8% capacitance retention after 10 000 cycles). This work provides a general strategy to manufacture robust graphene structural materials for energy storage applications in flexible and wearable electronics.
摘要：
具有高机械-电性能的还原氧化石墨烯(rGO)膜的可扩展生产是可穿戴电子设备和能量存储应用的理想候选。去除由组装过程产生的石墨烯膜中的结构不完整性(例如褶皱或空隙)将极大地优化其机械性能。然而,薄膜中密集堆叠的石墨烯片降低了它们的离子动力学，从而限制了它们的发展。这里,水平-纵向结构调节策略被证明可以产生增强的机械，导电和电容石墨烯薄膜。通常,二维（2D）大石墨烯片（LGS）在组装过程中诱导GO的规则堆叠，以减少皱纹，而一维（1D）单壁碳纳米管（SWCNT）与石墨烯片桥接，以加强多向插层并减少GO层的重新堆叠。LGS和SWCNT的同时结合协同地形成精细的微观结构，改善石墨烯片的排列，增加连续导电路径以促进电子传输，并扩大层间间距以促进电解质离子扩散。因此,获得的石墨烯薄膜是平坦的，并表现出显著增强的机械性能，电导率（38727Sm-1），以及比电容（232Fg-1）作为超级电容器电极，而不是原始的rGO薄膜。此外，由于综合性能的改善，由石墨烯膜基电极组装的柔性凝胶超级电容器显示出高能量密度，良好的灵活性和优异的循环稳定性（93.8％的电容保留后10000次循环）。这项工作提供了一种通用策略，可以为柔性和可穿戴电子设备中的储能应用制造坚固的石墨烯结构材料。
