In this work, for the first time, we measured the transport properties including rheology, thermal conductivity (TC), and electrical conductivity (EC) of the nanofluids of graphene quantum dots (GQDs) in glycerol and distilled water at various mass fractions and temperatures. The GQDs were prepared with the average particle size of 20 nm by one-step green pyrolysis of citric acid. The GQDs-glycerol suspensions behaved as shear-thinning or pseudoplastic fluids at low shear rates and temperatures. The viscosity of glycerol decreases by loading GQDs so that 49.97% reduction in viscosity of glycerol was achieved by loading of 2% GQDs for shear rate of 0.66 s−1 at 20 °C. The TC of distilled water increases about 9% when 2% GQDs were loaded at 298 K. Also, the TC of GQDs-glycerol suspensions increased exponentially with raising temperature. The EC of distilled water increases by loading GQDs through the formation of surface charge by polarization of GQDs in distilled water. The maximum EC enhancement for the nanofluid with mass fraction of 0.0004 was around 14,342% at 25 °C.

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