Synthesis of crystalline cerium dioxide hydrosol by a sol–gel method

A nano-cerium dioxide hydrosol was synthesized via a sol–gel process at the range of room temperature to 65 °C with the nonionic surfactant PVP (polyvinylpyrrolidone). The mixture solution of cerium nitrate and urea turned out a visible chemical reaction under the catalysis of ammonia. The X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) analyses indicated the colloidal ingredient and nano-crystal structural information. The colloid was crystalline face-centered cubic nano-structured cerium dioxide. The sizes of CeO2 colloids are in the range of several nanometers to 10 nm or more. The application of the hydrosol may focus on the ceria-based polishing agent for chemical mechanical polishing (CMP) process.