Multiwalled Carbon Nanotubes/Co_3O_4 Nanocomposites and Its Electrochemical Performance in Lithium Storage

摘要

Multiwalled carbon nanotubes(MWNTs)coated with a thick layer of Co_3O_4 nanocrystals were prepared through a facile and effective method for the first time,which combined the acid treatment MWNTs and in situ decomposition of Co(NO_3)_2 in n-hex-anol solution at 140 deg C.TEM images show that the MWNTs are nearly fully coated with a layer of Co_3O_4 with an average size of 8nm.The coating layer is 15-20 nm in thickness.The electrochemical performance in Li~+insertion and extraction reactions shows that the MWNTs/Co_3O_4 composites have larger lithium storage capacities and a better cycle-ability.