NiO nanowires in nanofluids based on a PDMS-type fluid†

Improving the efficiency of environmentally friendly energy sources such as solar energy is one of the basic objectives for developing the ecological transition required by our society. Thus, in this work, nanofluids based on NiO nanowires and a polydimethylsiloxane (PDMS) fluid are developed to improve the efficiency of parabolic trough-based concentrating solar power plants (CSP-PTC). To this end, NiO nanowires are successfully synthesized in our laboratory and used to prepare nanofluids. Their physical stability is thoroughly characterized. Subsequently, the properties of interest for the application of these nanofluids as heat transfer fluids are characterized. These properties were surface tension, density, dynamic viscosity, isobaric specific heat and thermal conductivity. Based on these properties, the efficiency improvement of CSP-PTC systems is estimated, achieving improvements of up to 5% with the designed nanofluids.