Low-temperature synthesis of Mn3O4 nanoparticles loaded on multi-walled carbon nanotubes and their application in electrochemical capacitors

A low-temperature, efficient and one-step deposition method, in which Mn(CH3COO)(2)center dot 4H(2)O serves as precursor and O-2 as oxidant, was employed to deposit Mn3O4 nanoparticles on multi-walled carbon nanotubes (MWCNTs) in ethanol solution at 150 and 200 degrees C. The resulting Mn3O4/MWCNT composites were characterized by means of different techniques including x-ray diffraction, x-ray photoelectron spectroscopy and transmission electron microscopy. It was indicated that the Mn3O4 nanoparticles were attached uniformly on MWCNTs with sizes less than 10 nm, and the loading amount of Mn3O4 could be tuned by changing the initial weight ratio of Mn(CH3COO)(2)center dot 4H(2)O/MWCNT. The electrochemical behavior of the Mn3O4/MWCNT composites was examined by cyclic voltammetry, and the result indicated the specific capacitance of the composite electrode was 330 F g(-1), nearly 18 times higher than that of the pure MWCNT electrode. The good performance of the as-prepared composites as electrode material may be attributed to the synergistic effects of the Mn3O4 nanoparticles and the MWCNTs.