Porous CuCo2O4/CuO microspheres and nanosheets as cathode materials for advanced hybrid supercapacitors
Dongsheng Liu, Yafei Liu, Enhui Bao, Xianglin Ren, Xiaohong Liu, Yang Xiang, Chunju Xu, Yi Li, Huiyu Chen
Abstract
The design of composite electrode material with mesoporous structure is a promising strategy for the assembly of high-performance supercapacitor device, and it may enhance the energy storage capability including the capacity, cycling stability, and energy density ( E d ). In this study, porous CuCo 2 O 4 /CuO microspheres (MSs) and nanosheets (NSs) were successfully prepared through different methods, respectively. These MSs and NSs exhibit battery-like feature with excellent electrochemical performance and is of great potential for electrochemical energy storage. The CuCo 2 O 4 /CuO MSs showed a specific capacity ( C s ) of 284.5C g −1 at 1 A g −1 and 217.0C g −1 at 10 A g −1 , while those NSs delivered even higher C s of 337.6C g −1 . To assess the potential of practical application, a hybrid supercapacitor (HSC) was assembled with CuCo 2 O 4 /CuO composite as cathode and activated carbon (AC) as anode, and this device could run under a high voltage of 0–1.7 V. The CuCo 2 O 4 /CuO MSs//AC HSC possessed an E d of 28.7 W h kg −1 under a power density ( P d ) of 0.9 kW kg −1 , while the NSs-based HSC delivered a higher E d of 38.8 W h kg −1 at 1.0 kW kg −1 . Moreover, both HSCs exhibited superior cycling performance throughout 3000 cycles at a high current density of 6 A g −1 . The present strategy is promising in synthesizing other transition metal oxides (TMOs)-based electrode materials with good electrochemical performance for further assembly of advanced HSC device.