Enhanced lithium storage performance of binary cooperative complementary CuO–Mn3O4 nanocomposites directly synthesized by hydrothermally controlled method

Abstract In this work, Mn3O4 nano-octahedrons and quasi-octahedron shaped CuO–Mn3O4 nanocomposites were prepared by hydrothermal reduction method. A “dissolution-recrystallization-cocrystallization” mechanism was applied to elucidate the growth process of quasi-octahedron shaped CuO–Mn3O4 nanocomposites. The obtained two Mn3O4 samples for their use in lithium-ion batteries were investigated. During cycling, the phase stability and charge-transfer behavior of Mn3O4 can be enhanced by introducing another cooperative complementary transition metal oxide. After 350 cycles, the formed CuO–Mn3O4 nanocomposites exhibit an essentially constant capacity of 1100 mA h g−1. It suggests the synergetic effects of binary cooperative complementary metal oxides can accelerate electron transfer that occurs between active material and substrate. At the same time, the formation of nano-bulges and nano-crevices on the surface of quasi-octahedron shaped nanostructure enhances the contact area, shortens the lithium diffusion pathway, facilitates the electrolyte to access into the electrode material and effectively reduces volume change during Li+ insertion/extraction process. This work presents a new strategy of Mn3O4 nanostructure doping with transition-metal ions and demonstrating its application feasibility for the preparation of high performance lithium ion batteries.