2D MoSe2-based nanofluids prepared by liquid phase exfoliation for heat transfer applications in concentrating solar power

Abstract

Concentrating solar power (CSP) is one of the most promising environmentally-friendly sources of energy for meeting global energy demands. One line of research intended to improve this kind of solar plants involves increasing the efficiency of the heat transfer fluid (HTF) used, one option being the use of nanofluids. Consequently, this study involves a methodology based on liquid phase exfoliation to prepare stable nanofluids based on 2D MoSe2. A surfactant was used to modify the ratio of the components of the fluid's surface tension in order to obtain a stable nanofluid. Five nanofluids were prepared based on MoSe2 nanosheets, Dowtherm A heat transfer fluid and the Triton X-100 surfactant. The stability of the nanofluids was analysed for a month. Lastly, their thermal properties were characterized. The best nanofluid presented improvements of 7% in isobaric specific heat, 4% in diffusivity and 11% in thermal conductivity. Therefore, these nanofluids would appear to provide a good starting point for creating an alternative to the conventional HTFs used in thermosolar plants. The study highlights the importance of optimizing the parameters of the ratio of the surface tension components, the kind of surfactant added and the methodology used to prepare the nanofluid.