Applicability of mono-nanofluid and hybrid-nanofluid as a technique to improve the performance of solar still: A critical review

The worldwide scarcity of potable water is the prime issue in the current scenario that led researchers to search for an alternative solution. The availability of water on Earth in the sea is abundant, but the total dissolved solid content is in the range of 35000 and 45000 ppm. To fulfill the need for potable water, necessary to desalinate the saline or sea, or impure water. The solar still is a solar energy-based ingenious device utilized to desalinate saline water. However, solar still is confronted with lower productivity. The use of water-based nanofluid is the most promising method to enhance the productivity of the solar still. The review presents the study of the impact of the type of nanofluid, the concentration of nanoparticles, and depths of nanofluid on the performance of solar still using state-of-art literature. The state-of-art literature on the use of nanofluid in solar still augmented with the various augmentations was also discussed. The summary of outcomes of various recent state-of-art-of liter-ature is presented in the form of tables. The perception of hybrid nanofluid and its benefits over the mono-nanofluid is discussed using various literature and its applicability in solar still was also reviewed. The key finding from the literature is presented in the conclusion section and the scope for future work is presented at the end.