Synthesis and Molecular Interaction Study of Polymer‐NiFe₂O₄ Nanofluids at Different Temperatures by Using Ultrasonic Waves of 2 and 5 MHz for Medical Applications

In this study, the sol–gel synthesis technique was used to create the pure nickel ferrite (NiFe 2 O 4 ) nanoparticles. Citric acid is utilized as a stabilizing agent to aid in the creation of nanoparticles and control the size and morphology of the nanoparticles. Nickel sulfate hexahydrate (Ni(SO 4 )⋅6H 2 O) and iron nitrate nonahydrate (Fe 2 (NO 3 ) 3 ⋅9H 2 O) are used as precursors. To improve the size and band gap of the resulting nanoparticle sample, ultraviolet (UV) characterization is performed. To create the homogenous solution known as PEG‐NiFe 2 O 4 nanofluids of 2% concentration and 0.6 g of nanoparticle powder were disseminated into 30 mL of polyethylene glycol (PEG) polymer and agitated for at least 4 h at 70°C. To evaluate the ultrasonic velocity, density, and viscosity at various temperatures (303–333 K), the acquired sample was poured into the ultrasonic interferometer cylinder of ultrasonic wave frequencies 2 and 5 MHz in addition, utilizing practical parameters like ultrasonic velocity, density, and viscosity, the associated ultrasonic parameters like adiabatic compressibility, acoustic impedance, and ultrasonic attenuation were calculated. The obtained results have been discussed in detail.