Influence of graphene nano-platelets dispersion on the thermo-physical properties of sunflower oil

Abstract

In this article, thermal stability, viscosity, density and surface tension of graphene nano-platelet dispersed in sunflower oil are experimentally determined by varying the graphene concentration (0.1-1.1 wt.%) and temperature (40-100°C). The SEM micrograph and the EDS spectra are used to characterize the graphene. Nanofluids are prepared by ultrasonication technique (two-step method) and the maximum thermal stability of about 280°C is achieved at 1.1 wt.% graphene nanofluids. The dynamic viscosity diminishes in an exponential shape in acquiescence with the Arrhenius equation and the densities of samples are characteristic with linear decrement in the estimated temperature range. Density and surface tension increase with the graphene concentration, while a reverse trend is observed with temperature raise. The maximum thermal stability, viscosity, density and surface tension is obtained in the nanofluid with 1.1 wt.% concentration and the minimum is obtained in the nanofluid with 0.1 wt.% concentration.

Keywords

• graphene
• thermal stability
• surface tension
• nanofluids
• sunflower oil