Experimental investigation of distilled water production performance of conventional solar stills using CaCl2·6H2O phase change material reinforced with SrCl2·6H2O and graphene-based nanoparticles

This study aims to enhance the performance of conventional single-slope basin-type solar stills by integrating phase change materials (PCMs) and nanoparticles. Calcium chloride hexahydrate, known for its high heat storage capacity, was selected as the primary PCM. Strontium chloride hexahydrate was added as a nucleating agent to address the supercooling tendency. Additionally, graphene oxide (GO) and graphene nanoplatelets (GNP), which have not been previously used in solar stills or compared for their performance, were incorporated into the PCM to utilize their photothermal properties and enhance solar energy absorption. The integration of GO and GNP with the PCM-nucleating agent combination resulted in daily total distilled water productions of 5424ml/m 2 and 5032 ml/m 2 , respectively. The integration of GO with the PCM-nucleating agent combination provided the most significant improvement in efficiency, with a 54.44 % increase compared to the standard still, a 15.4 % increase compared to the still using only the nucleating agent, and an 8 % increase compared to the still incorporating GNP.