▎ 摘　　要

A flexible 3D N-doped reduced graphene oxide (N-RGO)/carbon nanotube (CNT)-MnO2 hybrid film was constructed with outstanding supercapacitor, excellent oxygen reduction reaction (ORR) and good sensing performances. The resultant hybrid film possessed large specific capacitances of 418 F g(-1) and 209 mF cm(-2) in aqueous and solid electrolytes, and outstanding capacitance retentions of 95% and 94% were obtained for both electrolytes after experiencing 5000 cycles. A simple supercapacitor based on the resultant flexible hybrid film was further fabricated with a much smaller time constant tau(0) (0.38 s) than that of typical activated-carbon supercapacitors, suggesting a quick response frequency. Moreover, the assembled supercapacitor device showed high energy densities of 45.72 and 92.13 Wh kg(-1) and simultaneously sustained large power densities of 12,526 and 15873 W kg(-1) under a scan rate of 50 mV s(-1) in aqueous and solid electrolytes, respectively. Furthermore, the resultant flexible film showed excellent performance in the ORR and can also be used to assemble a strain sensor with an excellent sensing performance for bending strain. (C) 2020 The Chinese Ceramic Society. Production and hosting by Elsevier B.V.