Facile Fabrication of MCo 2 S 4 (M = Mn, Ni) Nanotube Arrays for High-Performance Supercapacitors

MCo 2 S 4 (M = Mn, Ni ) nanomaterials are attracting considerable attention because of their unique nanostructure, good redox properties, excellent theoretical capacitance, low cost and easy preparation. Herein, MCo 2 S 4 (M = Mn, Ni ) nanotube arrays have been fabricated by a one-pot hydrothermal method and could be used as conductive additive and binder-free electrodes for supercapacitors. The results show that the specific capacitance of MCo 2 S 4 (M = Mn or Ni ) nanotube arrays could reach as high as 2667 and 1623 F/g at the current density of 10 A/g, respectively, indicating high rate performance. Furthermore, the MnCo 2 S 4 nanotube arrays exhibited excellent cycling stability (68% of initial specific capacitance after 1800 cycles). These excellent electrochemical properties benefit from the synergistic effects of unique tubular microstructure and high conductivity of the samples. Graphical Abstract Schematic illustration of formation of MCo 2 S 4 (M = Mn, Ni)