Preparing Cu_2O Nanoparticles in Acid Solution Using High-energy Ball Milling

The copper powder was ball-milled in HCl solution(pH=2)by high-energy ball milling.Both milling balls and container were made of pure copper.The weight ratio of Cu balls with in diameter of 15mm to the weight of powder was 20:1,and all milling was carried out at a speed of 300r/min.The pure copper powder was transformed to Cu_2O fundmentally after 3h ball milling while the pure Cu_2O with the diameter of 50-100nm was obtained after 70h ball milling.The as-synthesized products were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM)and transmission electron microscope(TEM).The mechanism of the formation of Cu_2O and the effect of milling parameters on the formation of Cu_2O were discussed.