A facile method for synthesis of nanostructured copper (II) oxide by coprecipitation

Due to their versatility e wide range of physical and chemical properties, transition metal oxides are very promising as nanostructured materials. Copper oxides are indicated for applications in increasingly wider areas as gas sensing, catalysts, solar cells, electrochromic devices, and antimicrobial materials. In this study, copper (II) oxide nanoparticles were synthesized by the coprecipitation method from two precursors: copper sulfate and copper chloride. The evaluated precursor concentrations were 0.1 M and 0.2 M and temperatures were 50 °C and 75 °C. Different results were found, according to synthesis parameters and precursor used. Using copper sulfate as a precursor, a single phase of polycrystalline CuO could be obtained, and only a mixture of crystalline phases of CuO and cllinoatacamite (Cu2(OH)3Cl) were found using copper chloride as the precursor. A known polymorphism phenomenon was observed in clinoatacamite according to synthesis reaction parameters, and all three polymorphs were found mixed with CuO nanoparticles. Crystallite sizes of about 10 nm were found in this study, with leaf and rod-like nanostructured particles with dimensions range from 190 to 700 nm, and very good thermal stability. Under the synthesis conditions selected in this study, nanostructured materials made with copper sulfate precursor exhibited smaller crystallite sizes and better thermal stability. The coprecipitation method used was considered adequate to obtain nanostructured materials, with the advantages of being simple, fast and inexpensive.