Effect of carbonaceous materials on electrochemical properties of nano-sized Fe2O3-loaded carbon as a lithium battery negative electrode

Nano-sized Fe2O3-loaded carbon material was prepared by loading Fe2O3 on carbon using various carbonaceous materials. Carbonaceous materials strongly affected the electrochemical behavior of nano-sized Fe2O3-loaded carbon. Among the carbons used, nano-carbons such as acetylene black (AB), tubular carbon nanofibers (CNF), and platelet CNF provided larger capacities than other carbons. This may be due to the greater surface area of nano-carbon, which gives a greater distribution of nano-sized Fe2O3 particles than other carbons and delivers a greater capacity than other carbons. Investigation of the first-cycle materials by X-ray photoelectron spectroscopy (XPS) revealed that Fe2O3 was reduced to Fe metal in the charge process (reduction of Fe2O3), and, conversely, Fe metal was not completely oxidized to Fe2O3 during discharge (oxidation of Fe). This result may be due to the covering of non-conductive Li2O formed during charging.