Nickel-carbon composites toward supercapacitor and self-charging systems: A review

Developing highly efficient and low-cost supercapacitors as energy storage devices has been identified as one of the most prospective approaches for solving the intermittency and spatial unbalance problems related to the utilization of renewable clean energies (water, wind and solar). Electrode materials, as the core components in supercapacitors, require meticulous designing and tuning because they directly determine the performance of the supercapacitors. In recent years, nickel-carbon composites have been widely used as electrode materials for supercapacitors attributing to their low manufacturing cost, outstanding mechanical properties and excellent electrochemical performance including high specific capacitance and long cycle stability resulting from the strong compatibility and synergy between nickel and carbon. Even though researches on nickel-carbon composites for supercapacitors emerge in large numbers, there is still very few special reviews on the development of nickel-carbon composites for supercapacitors. To this end, in this paper, the research progress of nickel-carbon composites as electrode materials for supercapacitors and their applications in self-charging are reviewed. Firstly, the research background and significance of supercapacitors are briefly introduced. Secondly, the energy storage mechanisms of the high-performance nickel-carbon composites and their structural design are presented. Thirdly, recent research progress of different types of nickel-carbon composites as electrode materials for high-performance supercapacitors including advantages, problems and future development directions are elaborately described. Finally, the applications of nickel-carbon composites-based supercapacitors in the field of self-charging energy storage are demonstrated. We believe this paper can provide guidance for the design and application of high-performance nickel-carbon composites as supercapacitors.