Mesoporous 3D ZnO-NiO architectures for high-performance supercapacitor electrode materials

3D ZnO-NiO mesoporous architectures were synthesized through annealing the zinc hydroxide carbonate-nickel hydroxide carbonate composite precursor, which was prepared via a one-pot hydrothermal route. More importantly, we successfully explore the application of the 3D ZnO-NiO composite mesoporous architectures as electrochemical capacitors. Electrochemical study presented that the as-prepared 3D ZnO-NiO composites under different annealing conditions have different electrochemical supercapacitor properties. The as-synthesized sample obtained at 400 degrees C shows a high specific capacitance of 2498 F g(-1) at a current density of 2.6 A g(-1), a good rate capability at high current densities and an excellent long-term cycling stability (about 3.0% loss of the maximum specific capacitance after 2000 cycles), which are mainly attributed to its morphological characteristics of mesoporous and nanosheet self-assembling architectures, as well as a rational composition of the two constituents. These results suggest that such 3D ZnO-NiO mesoporous architectures are promising materials for supercapacitors.