Chemical Engineering Journal, Vol.231, 365-372, 2013
Preparation, characterization, and rheological properties of graphene-glycerol nanofluids
We report the production of high quality few-layer nanosheets of graphene from burning magnesium metal in dry ice. The prepared graphene sheets were characterized by nine methods, namely transmission electron microscopy, high resolution transmission emission electron microscopy, scanning electron microscopy, Raman spectroscopy, Fourier Transform-Infrared spectroscopy, energy-dispersive X-ray analysis, powder X-ray diffraction, Boehms titration, and N-2 adsorption-desorption technique. The 'theological properties of graphene-glycerol nanofluids were measured at different mass fractions (0.0025-0.0200) and temperatures (20-60 degrees C). To the best of our knowledge, this is the first work on rheological properties of graphene-glycerol nanofluids. The experimental results showed that the viscosity of graphene-glycerol nanofluids increases with increasing the mass fraction and decreases with increasing temperature. Our results clearly showed a very strong shear thinning behavior of the graphene-glycerol nanofluids. A 401.49% enhancement in viscosity of glycerol was achieved by loading of 2% graphene nanosheets at shear rate 6.32 s(-1) and 20 degrees C. (C) 2013 Elsevier B.V. All rights reserved.