Water is the most important resource for mankind. Yet, 97% of the earth’s surface water is seawater in the oceans and only 3% is fresh water in ground water. Therefore, different kinds of water desalination and treatment technologies have been developed, and water distillation is a basic process of evaporating water in order to leave behind impurities such as minerals, pollutants, and other contaminants. Although distillation is known as an effective water treatment process that removes many kinds of bacteria and inorganic chemicals and heavy metals, a large amount of conventional energy and non-renewable resources are consumed for this process. The objective of this thesis is to develop water distillation technology that uses plentiful and free solar energy by utilizing different functional nanomaterials. Double layered functional materials (exfoliated graphite and carbon foam) were used for sunlight absorption and heat localization which enable significantly improved water evaporation efficiency. A test chamber was built for heat loss minimization through the side surfaces and an indoor cost-effective solar simulator was designed to generate similar incident lights of solar irradiation using FRED simulation to verify the results. This indoor solar simulator allowed to perform consistent and reliable tests. The double layered materials were characterized using electron microscopes and various material analysis. The performance of the developed system was examined by measuring the temperature profile of the bulk water and the mass of evaporated water. The purified water produced by the developed distillation system was examined using two different analysis methods. The double layered functional materials localize heat within top layer and it led to enhance the evaporation rate by a factor of five (5) under one (1) sun irradiation. The heat localization was also demonstrated using a heat transfer simulation. Although a further water quality study needs to be carried out, it was demonstrated that the developed system can be promising in a next generation solar distillation process.
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