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Abstract: The practical applications of wearable electronics rely on the successful development of flexible and integrable energy devices with small footprints. This work reports a completely new type of graphite foam made of strategically created superstructures with covalently attached diverging microtubes, and their applications as electrode supports for binder‐free and additive‐free flexible supercapacitors. Because of the enhanced volumetric surface areas compared to conventional graphite foams, a high loading of pseudocapacitive materials (Mn3O4, 3.91 mg cm−2, 78 wt%) is achieved. The supercapacitors provide areal capacitances as high as 820 mF cm−2 at 1 mV s−1, while still maintaining high rate capability and 88% retention of capacitance after 3000 continuous charging and discharging cycles. When assembled as all‐solid‐state flexible symmetric supercapacitors, they offer one of the highest full‐cell capacitances (191 mF cm−2) among similar manganese oxide/graphene foams, and retain 80% capacitance after 1000 mechanical cycles. The potential of such flexible supercapacitors is also manifested by directly powering electric nanomotors that can trace along letters “U” and T,” which is the first demonstration of flexible supercapacitors for wireless/portable nanomanipulation systems. This work could inspire a new paradigm in designing and creating 3D porous micro/nanosuperstructures for an array of self‐powered electronic and nanomechanical applications. [ABSTRACT FROM AUTHOR]

Flexible energy storage devices play a pivotal role in realizing the full potential of flexible electronics. This work presents high-performance, all-solid-state, flexible supercapacitors by employing an innovative multilevel porous graphite foam (MPG). MPGs exhibit superior properties, such as large specific surface area, high electric conductivity, low mass density, high loading efficiency of pseudocapacitive materials, and controlled corrugations for accommodating mechanical strains. When loaded with pseudocapacitive manganese oxide (Mn3O4), the MPG/Mn3O4 (MPGM) composites achieve a specific capacitance of 538 F g−1 (1 mV s−1) and 260 F g−1 (1 mV s−1) based on the mass of pure Mn3O4 and entire electrode composite, respectively. Both are among the best of Mn3O4-based supercapacitors. The MPGM is mechanically robust and can go through 1000 mechanical bending cycles with only 1.5% change in electric resistance. When integrated as all-solid-state symmetric supercapacitors, they offer a full cell specific capacitance as high as 53 F g−1 based on the entire electrode and retain 80% of capacitance after 1000 continuous mechanical bending cycles. Furthermore, the all-solid-state flexible supercapacitors are incorporated with strain sensors into self-powered flexible devices for detection of both coarse and fine motions on human skins, i.e., those from finger bending and heart beating. [ABSTRACT FROM AUTHOR]

All‐solid‐state flexible supercapacitors based on strategically created three‐dimensional hierarchically porous graphite foams are reported by Donglei Fan and co‐workers in article number 1702738. The supercapacitors exhibit ultrahigh specific capacitances based on the entire electrode weight and retain 80% of capacitance after 1000 continuous bending cycles. They can be seamlessly integrated with strain sensors for self‐powered detections of strains from skins, including carotid artery pulses and finger bending. [ABSTRACT FROM AUTHOR]