Sb-MOx-C(M = Al, Ti, or Mo) Nanocomposite Anodes for Lithium-Ion Batteries

Sb-MOx-C (M = Al, Ti, and Mo) nanocomposites have been synthesized by a mechanochemical reduction of Sb2O3 with, respectively, Al, Ti, and Mo, in the presence of carbon (acetylene black). X-ray diffraction (.XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM) data reveal that these nanocomposites are composed of uniformly dispersed nanostructured antimony in the amorphous Al2O3, TiO2 or MoO3 matrix, along with conductive carbon. These composite electrodes exhibit excellent electrochemical cycling performance and rate capability in lithium cells, compared to pure antimony. Among the three Sb-MOx-C systems studied, the M = Al system with Al2O3 Lis the amorphous phase exhibits the best electrochemical performance, offering a capacity of > 430 mAh/g after 100 cycles. The improvement in the cycling performance, compared to that of pure antimony, is attributed to a homogeneous distribution of the electrochemically active Sb nanoparticles within the ceramic oxide and conductive carbon matrix, resulting in good electrical contact with the current collector, as well as a mechanical buffering effect on the volume expansion-contraction that occurs during cycling.