Preparation and thermal conductivity investigation of reduced graphene oxide-ZnO nanocomposite-based nanofluid synthesised by ultrasound-assisted method
Heena Mandhare, Divya P. Barai, Bharat A. Bhanvase, Virendra Kumar Saharan
Abstract
Preparation of water-based nanofluid containing reduced graphene oxide-zinc oxide (rGO-ZnO) nanocomposite particles synthesised by ultrasonic-assisted method has been carried out in this work. Energy-dispersive X-ray spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray pPhotoelectron sSpectroscopyand Raman spectroscopy were used to confirm the successful formation of the nanocomposite. The reduction of GO and attachment of the ZnO nanoparticles to it was evident from all the characterisation techniques. For 0.1 vol.% of rGO-ZnO nanocomposite-based nanofluid, the thermal conductivity was found to be 2.95 W/mK at 50°C. It further increased with increase in temperature and concentration of the nanofluid, for which a new correlation has been proposed, which can satisfactorily predict the behaviour. Also, comparison of thermal conductivity of rGO-ZnO nanocomposite-based nanofluid with nanofluids containing rGO, ZnO nanoparticles and other rGO-based nanocomposite particles has been done. This study suggests a possible application of the rGO-ZnO nanocomposite-based nanofluid for various heat transfer applications.