The Application of Carbon-Based Materials in Solar Harvesting for the Production of Water. In solar interfacial evaporation the photothermal material facilitate distillation process at the liquid-air interface. The photothermal material are optically active metals or carbon material such as carbon nanotubes, graphene oxide. Properties of the phothothermal material include floating, thermal insulating ability and porosity. In this study metal free carbon based material were synthesized and tested for photothermal conversion and efficiency. The spherical carbon materials were prepared by CVD method  and these materials were used as light absorbing material to assist the evaporation process.