Magneto-thermo-optic characterization of ZnFe₂O₄/Ag/AgCl nanocomposite/water nanofluid

Herein, we report how the magnetic tunability of thermal diffusivity of nanofluids of zinc ferrite/silver/silver chloride in water can be achieved. High resolution transmission electron microscopy, X-ray Photoelectron Spectroscopy and Brunauer–Emmett–Teller surface area analysis are performed to validate the characteristics and suitability of the sample in designing the magneto-thermo-optic characteristics. The dual beam thermal lens technique was employed for the first-time estimation of the thermal diffusivity of nanofluids in the presence of an external magnetic field which demonstrated up to a ten-fold increase in thermal diffusivity of nanofluid [ \(14.5\times {10}^{-7}{m}^{2}{s}^{-1}\) $14.5\times {10}^{-7}{m}^2{s}^{-1}$ ] than that of base fluid water attributed to the clustering/chaining effects. The optical microscopic and field emission scanning electron microscopic images of the nanofluid films dried in the presence of magnetic field pointed to the dominant effects of percolation due to the aggregate formation of nanoparticles in attributing magnetic tunability of thermal diffusivity. Thus zinc ferrite/silver/silver chloride nanofluid can be tailored for several heat transfer applications such as heat sinks in electronics, magnetic hyperthermia and photothermal therapy.