In this study, we report the synthesis of MnxNi1-xO and MnyCo1-yO alloy nanoparticles by the thermal decomposition of the metal precursor in a surfactant. The synthesized particles were expected to have enhanced stability and their magnetic properties were expected to be different from those of particles synthesized in our previous experiment. We investigated the magnetic properties of the particles by using a superconducting quantum interference device (SQUID), after characterizing them by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and other measurement techniques. Also, the synthesized nanoparticles were applied into anode materials in lithium ion batteries. The characteristic conversion reaction associated with Li uptake was observed and the anode performance became more improved according to an increase of Ni content. Especially, the higher Ni content (Mn0.33Ni0.66O) electrode exhibited a large reversible capacity (650 mAh g-1), a better initial efficiency (56%), an improved rate and cycle performance. From electrochemical impedance spectroscopy, the improved anode performance was ascribed to higher electrical/electrolyte conductivity or improved surface film property.
