Core/shell (Cu/Cu2O) nanotubes as high performance anode materials for Li-ion rechargeable batteries

Abstract

A direct electrodeposition technique for very high quality Cu nanotube arrays and subsequent conversion of the deposited Cu into Cu2O has been developed. The Cu2O nanotube arrays have high capacity, high cyclability and high rate capability. The cycling performance of Cu2O nanotubes show a high level of structural integrity with capacity retention even after 94 cycles when cycled at 1.67 mA/cm2. The outstanding electrochemical performance of the Cu2O nanotubes comes from high surface area, easy infiltration of electrolytes, high electrical conductivity of Cu core support and structural integrity of the oxide shell active material. The Cu2O nanotubes also eliminate the requirement of ancillary materials currently used in Li-ion batteries, such as carbon particles to increase conductivity. The easy fabrication and performance of Cu2O nanotube arrays may make them suitable for next generation Li-ion batteries.