Self-Assembled Mn₃O₄ Nano-Clusters over Carbon Nanotube Threads with Enhanced Supercapacitor Performance

Abstract

A well defined carbon nanotube threaded trimanganese tetroxide (Mn3O4@CNT) nanocomposite has been fabricated through a facile hydrothermal route using acetylacetone as a chelating agent. The Mn3O4 nano-clusters are formed by the self-assembly of numerous Mn3O4 nanostructures and the CNTs are uniformly decorated on the body of Mn3O4 nano-clusters to improve the conductivity of the composite. The porous and well-designed architecture of the Mn3O4@CNT composite could be expected to offer more electroactive sites for pseudocapacitive reactions and shorten the transportation path for the electrolyte ions. Due to these properties as well as the synergistic effect of CNTs and Mn3O4 nano-clusters, the as-synthesized Mn3O4@CNT composite, which was primarily used as a pseudocapacitive material, showed a higher specific capacitance of 81.9 F g(-1) at a current density of 0.6 A g(-1) with good cycling stability. The delivered capacitance of the composite is comparatively higher than that of the pristine Mn3O4 (53.5 F g(-1)). The facile preparation approach to balance the higher electrochemical properties of the transition metal oxides with highly conductive carbon nanotubes provides the potential for the development of novel nanocomposites for energy storage devices.