Novel surface modification strategies for enhanced CeO2 nanoparticle dispersion and suspension stability

Abstract

This work aims to modify the surface characteristics of cerium oxide (ceria, CeO2) nanoparticles using different surface modification strategies for improved CeO2 nanoparticle dispersion and suspension stability. Analysis and discussion were conducted on the two surface modification processes used by a cationic surfactant like hexadecyl cetyltrimethylammonium bromide (CTAB) and a silane agent like tetraethyl orthosilicate (TEOS). Untreated CeO2 was used as reference material. The dispersion effect of surface-modified CeO2 nanoparticles at different pHs was determined by zeta potential measurements. Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Particle size analysis (PSA), Thermogravimetric analysis (TGA), Scanning electron microscope (SEM), Brunauer–Emmett–Teller analysis (BET), and X-ray diffraction (XRD) were used to confirm the efficacy of the surface modification of CeO2 nanoparticles. First, the results obtained in this experimental work demonstrate that both advanced modifications greatly enhance the dispersion and suspension stability of surface-modified CeO2 nanoparticles in comparison with untreated CeO2 nanoparticles. Second, it is also shown that the surface-modified CeO2 nanoparticles obtained through a silanization surface process with TEOS silane agent had a better dispersion effect and dispersion stability than the surface-modified CeO2 nanoparticles obtained by surface modification with CTAB cationic surfactant. These results can help better understand how advanced surface modifications can assist the application of well-dispersed CeO2 nanoparticles in technological applications.