MOFs assisted construction of Ni@NiOx/C nanosheets with tunable porous structure for high performance supercapacitors

High specific surface area (SSA) and optimized porous structures are necessary for supercapacitors electrodes. MOFs have porous structure which make them potential candidates for electrodes materials. Here, a MOF derivative with Ni@NiOx nanoparticles embedded in porous carbon nanosheets (Ni@NiOx/C) is prepared by hydrothermal method and carbonization process. Among them, the porous structure is tuned by the ZnO templates. Results show that the amount of doped ZnO nanoparticles can affect the morphology, porous structure and electrochemical properties of Ni@NiOx/C nanosheets electrodes. In three electrode system, the Ni@NiOx/C-2 electrode has a high specific capacitance of 752 F g −1 (at 1 A g −1 ) and prominent rate performance (the initial capacitance retains 56% when the current density increased to 100 A g −1 ). After 10,000 cycles, 99% of the initial capacitance is maintained. The assembled asymmetric device (Ni@NiOx/C-2//AC) also exhibits a high-power density (15,840 W kg −1 ). • The MOF derived Ni@NiOx/C materials possess tunable porous structure. • The effect of ZnO doping on the pore size distribution is analyzed in detail. • The highest specific capacitance of the electrodes is 752 F g −1 . • The electrode displays excellent cyclic stability.