MnO2@NiO nanosheets@nanowires hierarchical structures with enhanced supercapacitive properties
- 6 Downloads
Transitional metal oxides are demonstrated as promising candidates for pseudocapacitive electrode materials for use in high-performance supercapacitors. Here, we report a rational design of the MnO2@NiO nanosheets@nanowires hybrid structure. The as-prepared hierarchical structure shows highly uniformity and interconnection between ultrathin MnO2 nanosheets and NiO nanowires. The well-designed MnO2@NiO is directly used as binder-free electrode and exhibits a high specific capacitance (374.6 F g−1 at a current density of 0.25 A g−1; areal capacitance of 1.3 F cm−2), good rate capability, and excellent cycling stability (92.7% capacitance retention after 5000 charge/discharge cycles). An asymmetric supercapacitor (ASC) is assembled using the MnO2@NiO as the positive electrode and activated microwave exfoliated graphite oxide as the negative electrode. The assembled ASC shows excellent electrochemical performance with an energy density of 15.4 W kg−1 and a maximum power density of 9360 W kg−1. These analytical and experimental results clearly indicate the advantages of multicomponent hierarchical core–shell structure for engineering high-performance electrochemical capacitors.
The financial support funded by Chongqing Special Postdoctoral Science Foundation (XmT2018043) was highly appreciated. FL acknowledges the support and funding from China Scholarship Council (CSC).
Compliance with ethical standards
Conflict of interest
All authors listed have declared that they have no conflict of interest.