Synthesis and application of reducing graphene oxide based nanocomposite materials to improve the solar thermal absorption efficiency for distilling saline water into fresh water

Abstract

This work presents the preparation and characterization of some nanocomposite materials based on reduced graphene oxide (rGO) (Al₂O₃/rGO, Fe₃O₄/rGO, Fe₃O₄–Al₂O₃/rGO). Thermal sorption ability of prepared nanocomposite materials in salty water were measured. Results showed that all investigated materials that were dispersed in salty water raised the thermal absorption ability of solutions. Fe₃O₄-Al₂O₃/rGO gived the highest thermal absorption efficiency (the temperature difference between the blank sample and the sample containing Fe₃O₄-Al₂O₃/rGO with content of 0.5 mg/mL is 8°C). The thermal sorption increased with increasing the concentration of materials in solution and the suitable concentration of 5 mg/mL was found. The addition of Fe₃O₄ increased the thermal sorption and created magnetic property of material. Fe₃O₄-Al₂O₃/rGO was recovered by magnet with high yield up to 98%; Olny a minor decrease in thermal sorption ability of recovered material was abserved. The distillation rate of salty water dispersed Fe₃O₄-Al₂O₃/rGO using solar energy was four times higher than without dispersing it. The results showed that these nanocomposite materials can be used to increase the efficiency of thermal absorption in the process of distilling salty water into fresh water.