Published Paper Details:

Ferrofluids are colloidal suspensions of magnetic nanoparticles in carrier liquids that exhibit unique magnetorheological properties. Kerosene-based ferrofluids containing oleic acid-coated magnetite (Fe?O?) nanoparticles have gained attention due to their excellent thermal stability, low volatility, and superior dispersion characteristics. This review examines the synthesis methodologies, characterization techniques, and diverse applications of oleic acid-coated kerosene-based Fe?O? ferrofluids. We analyzed chemical co-precipitation and thermal decomposition methods for Fe?O? nanoparticle synthesis, emphasizing oleic acid's role as a surfactant in achieving stable colloidal dispersions. Characterization approaches discussed include X-ray diffraction (XRD) for phase identification, transmission electron microscopy (TEM) for morphological analysis, Fourier transform infrared spectroscopy (FTIR) for confirming oleic acid coating, vibrating sample magnetometry (VSM) for magnetic property evaluation, and rheological measurements for assessing flow behavior. The chemical bonding mechanisms between oleic acid and magnetite surfaces are critically analyzed. The review highlights how oleic acid surface modification prevents particle agglomeration and enhances long-term stability in non-polar kerosene carriers. Characterization reveals distinct patterns in XRD peaks, magnetization curves, and viscosity-temperature relationships governing ferrofluid performance. Kerosene-based ferrofluids demonstrate superior performance in heat transfer enhancement for cooling systems, damping applications in shock absorbers and vibration control, and magnetic fluid sealing technology for rotary seals and vacuum feedthroughs. Emerging biomedical applications include drug delivery and magnetic hyperthermia therapy. This review synthesizes current knowledge on oleic acid-coated kerosene-based Fe?O? ferrofluids and identifies future research opportunities in nanoparticle size optimization, surface chemistry modification, and application-specific formulations, serving as a resource for researchers working on ferrofluid development across technological domains.