Abstract
The CdO/por-CdS/CdS heterostructures were formed by a three-step electrochemical treatment method, which included cathodic etching, anodic deposition, and simple chemical etching. As a result, a porous layer of por-CdS was synthesized on the surface of CdS, onto which a layer of CdO was deposited. An interesting outcome of the research is the formation of doughnut-shaped CdO crystallites. These crystallites demonstrate a large effective surface area and may be applied as magnetic or photocatalytic materials. A mechanism for the formation of doughnut-like crystallites is proposed. EDX and RAMAN analysis confirmed the presence of CdO on the surface in both crystalline and amorphous states.