Simple and Rapid One-Step Electrochemical Synthesis of Nanogranular Cu₂O Films

In the present work, we report a simple experimental strategy for the one-step electrochemical synthesis of nanogranular Cu₂O films by copper anodization in fluoride-containing ethylene glycol media. Microscopic exploration using field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM), shows the formation of spherical shape grains with sizes ranging from 20 to 40 nm. Raman and X-Ray Photoemission Spectroscopy (XPS) results indicate that only Cu^I oxide is obtained. A band gap energy E_g=2.01 eV is estimated from UV–vis reflectance spectroscopy indicating that an indirect transition mechanism between semiconductor bands takes place. These evidences indicate that the present synthesis of nanogranular Cu₂O films is a promising method for obtaining improved properties of materials for the design of photoelectronic devices.