Preparation Of Cupric Oxide Nanowires And Its Lithium Storage Performance

In recent years, lithium-ion batteries as a kind of green and clean energy,has interested many scientists. The industrialization of lithium-ion batteriesalso gradually matured. But the carbon anode materials which have beenindustrialized have the low specific capacity and bad cycle stability. Thepurpose of this subject is to find a kind of material to instead of the carbonanode materials. CuO as the anode material has the perfect cycle stability. Andits theoretical specific capacity is675mAh/g, which is two times than thecarbon anode materials. Therefore we use simple synthetic routeto which isthermal oxidation method to prepare CuO nanowires and test its lithiumstorage performance.In this paper, we use thermal oxidation method to prepare CuO nanowires.CuO nanowires grow on the Cu foil perpendicularly. The root of CuOnanowires is thick and its tip is thin. The oxide layer contains different oxides,they are CuO nanowire, layer of CuO, Cu₂O layer from top to bottom. And weinvestigate the parameters which influence the morphology of CuO nanowires, such as the oxidation temperature, oxidation time, heating rate, thickness ofcopper foil, different substrate. Longer oxidation time, slower heating rate and1mm thickness of copper foil are favourable toward promoting the growth ofCuO nanowires. And500℃is the optimal oxidation temperature. Based onthese conclutions, we suggest that the growth mechanism of CuO nanowireswhich are prepared by thermal oxidation is tip growth theory. Substantialstress exists on the CuO–Cu₂O interface or phase boundaries due todifferences in their crystallographic structures.The products are dealed with concentrated ammonia to change all theCu₂O into CuO. Then we get the CuO nanowires which diameter is reducedand enwind into globe. When the current density is50mA/g, its specificcapacity is550mAh/g, which more than1.5times the capacity of commercialcarbon electrodes. And it has perfect cycle stability.