Integrated design of electrospun cellulose-based 3D Co and CNT inserted porous carbon materials for supercapacitor and HER

Based on the features of cellulose-based carbon materials, integrating metal–organic framework (MOF) and polymers in cellulose is in favor of the electrochemical performance for supercapacitor and hydrogen evolution reaction (HER). In this work, a three dimensional (3D) porous carbon material inserted by carbon nanotubes (CNT) and Co particles was designed by an electrospinning and calcination technology. During the calcination process, MOF-74 as both nanocatalysts and carbon sources was converted to CNT and Co particles, meanwhile, CA-PVDF fibrous membranes were pyrolyzed into the porous carbon, leading to the novel multilevel structures and specific C/Co component. The type (PAN, PVDF, PVP) and mass ratio (0:1, 1:2, 2:1, 1:0) of polymers were optimized to improve the electrochemical performance. As a result, due to the rich defects from CNT, the high specific areas caused by PVDF, as well as the specific activity of Co particles, the high specific capacitance of 169.50 F g−1 was obtained at 0.5 A g−1 for CAF(2:1)CT within -1.0–0 V. CAF(2:1)C showed acceptable HER catalytic activity. Additionally, an asymmetric solid-state supercapacitor (CAF(2:1)C//CAF(2:1)CT) was built and delivered a high energy density of 25.69 Wh kg−1, a superb cycling life during 10000 cycles, as well as a necessary practicality in circuit. This work proposed a novel hybrid biomass based carbon material, which can provide a reference for the design of electrode materials and catalysts in other fields.