Controlled Preparation of δ-Al\(_2\)O\(_3\) Nanoparticles Using Oil-in-Water Microemulsion method (O/W)

Abstract

Alumina nanoparticles have attracted considerable attention as advanced materials due to their promising properties for applications in catalysis, electronics, adsorption, and biomedicine. Traditional synthesis methods for alumina particles show several limitations, such as irregular morphology, low dispersibility, and a narrow range of application. The oil-in-water (O/W) microemulsion process was used to synthesize alumina. The effect of the amount of alumina precursor, aluminum isopropoxide, and surfactant, Tween 40, was investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with EDX. The results of the structural analysis indicate that the synthesized alumina powders are δ-Al₂O₃ and showed spherical nanoparticles. A decrease in particle size was observed as the amount of Tween 40 varied from 2.72% to 5.44% and increased with the amount of aluminum isopropoxide. These results demonstrated that the oil-in-water microemulsion method provided an effective route for controlling the morphology, size and dispersibility of good purity alumina nanoparticles.