Flexible micro-supercapacitors fabricated from MnO2 nanosheet/graphene composites with black phosphorus additive

Supercapacitors are widely used for powering flexible/wearable electronics owing to their excellent charge storage capabilities. In this study, MnO2 nanosheets were grown on the surface of graphene using a simple water bath method to prepare graphene/MnO2 composites for fabricating supercapacitors. In addition, two-dimensional black phosphorus was introduced as an additive into the electronic ink based on the as-prepared graphene/MnO2 composites. The characterization and electrochemical analyses results showed that adding black phosphorus considerably improved the capacitive performance of the material, yielding a high specific capacitance of 241.5 F g(-1) at 0.1 A g(-1) and an impressive rate capability improvement from 52.5% to 80.3%. Then the micro-supercapacitor having an area-specific capacitance of 20.15 mF cm(-2) at a scanning rate of 2 mV s(-1) was uti-lized to demonstrate the practical applicability of this material. To further evaluate the practical applicability of this micro-supercapacitor, the micro-supercapacitor was integrated with a flexible thin-film pressure sensor on paper and cloth through screen printing.

Automated summary

In this study, graphene/MnO2 composites were prepared by growing MnO2 nanosheets on the surface of graphene using a water bath method, and the addition of black phosphorus was found to significantly improve the capacitive performance of the material. The fabricated micro-supercapacitor demonstrated high specific capacitance and was integrated with a flexible thin-film pressure sensor for practical applications.