Preparation, characterization, stability, and thermal conductivity of rGO-Fe3O4-TiO2 hybrid nanofluid: An experimental study

In the present study, ternary rGO-Fe3O4-TiO2 nanocomposites was produced using a straightforward sol-gel technique. The nanofluids are synthesized using rGO-Fe3O4-TiO2 hybrid nanoparticles suspended in ethylene glycol (EG). Ternary rGO-Fe3O4-TiO2 nanocomposite (0.01-0.25 mass. %) were dispersed in EG acquiring stable nanofluids. The ternary rGO-Fe3O4-TiO2 nanocomposite present in the colloidal phase has been categorized by MR, SEM, EDX, XRD, and Zeta potential. At varying temperatures between 25 and 60 degrees C, the thermal conductivity was explored. Experimental results show that the stability of all the studied rGO-Fe3O4-TiO2/EG nanofluid samples was above 52.04 mV. Enhancement in thermal conductivity for rGO-Fe3O4-TiO2/EG nanofluids significantly increases with mass concentration and temperature, with an enhancement of 133% at 60 degrees C for 0.25 wt%. The best R-2 coefficient of determination estimated at 25 degrees C, 30 degrees C, 40 degrees C. 50 degrees C, and 60 degrees C was 95.6%, 98.2%, 95.4%, 97.6%, and 99.0%. Therefore, the investigated ternary hybrid nanofluid can be utilized for both heating and cooling applications with long term stability. (C) 2020 Elsevier B.V. All rights reserved.