Effect of CuO on the electrochemical activity of Li_2MnO_3

摘要

A new effect to induce the electrochemical activity of Li_2MnO_3 was found. The samples prepared by co-precipitation consisted of Li_2MnO_3 and CuO phases. The particle size of Li_2MnO_3 was much smaller than that of CuO by using TEM observation equipped with EDX. The specific charge and discharge capacity increased with the content of CuO, while maintaining the electrochemical characters of Li_2MnO_3. The ab-initio electronic structure calculation was carried out and the densities of states (DOS) were obtained for Cu-containing Li_2MnO_3 supercell and Li_2MnO_3. On basis of experimental and calculated results, a partial replacing Mn by Cu could improve the electrical property of Li_2MnO_3. A possible reason of the effect is that coexisting with CuO depressed the kinetic barrier of the electrode reaction for Li_2MnO_3.