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

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.