Three-dimensional MXene/BCN microflowers for wearable all-solid-state microsupercapacitors

Modified MXene (Ti(3)C(2)Tx) is attractive as a flexible electrode for wearable energy storage devices. In this work, a convenient and effective method was proposed to change the conventional 2D boron carbon nitride (BCN) nanosheets into three-dimensional 3D BCN microspheres that were obtained by tube furnace drying under N-2 flow and annealing. Then, the MXene/BCN microflowers were applied to all-solid-state flexible microsupercapacitors (MSCs) as a high-performance electrode material. It was found that the areal capacitance can reach up to 89 mF cm(-2) for a single MSC under 0.5 mA cm(-2). Furthermore, the MSCs can achieve remarkable mechanical flexibility such that the capacitance will not be evidently decreased even after bending by up to 180 degrees. In addition, 90.1% capacity retention was obtained even after 10 000 cycles and the highest energy density and power density reached 0.0124 mW h cm(-2) (volumetric energy density of approximately 17.7 mW h cm(-3)) and 3.1 mW cm(-2) (volumetric power density of approximately 4.5 W cm(-3)). These results demonstrate the synthesis of MXene/BCN composite materials with excellent power density and large scalability and can provide distinctive insights into high-performance flexible device storage systems.

Automated summary

The research successfully synthesized MXene/BCN composite materials and applied them to flexible microsupercapacitors, showing high areal capacitance and remarkable mechanical flexibility.