Boron and nitrogen Co-doped holey graphene aerogels with rich B–N motifs for flexible supercapacitors
© 2019 Elsevier Ltd Boron and Nitrogen co-doped holey graphene aerogels (BN-HGA) are fabricated using ammonia borane as triple-functional precursor. The as-prepared BN-HGA possesses high specific surface area (249 m2 g−1) and rich B–N motifs with high surface polarity, which contributes to the rich and stable redox sites for the enhanced pseudo-capacitance. Moreover, the high hydrogen content in the ammonia borane cultures a reducing environment to preserve the integrity of carbon matrix, which gives rise to the high electronic conductivity. In addition, the well-developed hierarchically porous structure facilitates the ion diffusion in the electrode. Thanks to these structural merits, the BN-HGA electrode furnishes good specific capacitance of 456 F g−1 at 1 A g−1 in three-electrode systems using sulfuric acid as electrolyte. Meanwhile, the all-solid-state flexible supercapacitors based on the symmetric BN-HGA electrodes demonstrate high specific capacitance (345 mF cm −2 at 1 mA cm −2) and outstanding rate performance (80% retention at 20 mA cm −2). Furthermore, the flexible supercapacitor exhibits pleasant flexibility with marginable capacity loss as bent to arbitrary angles, which endows it a promising device for wearable energy storage.