Prospective of graphene oxide based photothermal frameworks as interfacial water evaporator for clean water production

The future of our entire civilisation is enormously dependent on the availability of clean water for nourishment of living being. Desalination using solar energy for example photothermal water evaporation is an innovative method for production of freshwater. Development of self-assembled multifunctional photothermal materials is considered as reconciliation between solar energy harvesting and sustainable energy and environmental applications. In photothermal water evaporation method, nano enabled photothermal materials introduced into a floatable structure can stimulate localised heating effect in presence of solar energy for water evaporation. Efficient design of self-assembly enable it to exhibit synergistic photothermal conversion, floatable porous structure for efficient capillary action enabling water transmission and quick steam escape pathways. This chapter includes important latest discoveries related to the growing applications of customized graphene based interfacial photothermal frameworks. A comprehensive overview of the various criteria for selection of graphene oxide photothermal material was discussed. Diverse properties like light absorption, role of electronic band structure, thermal vibration and effective refractive index for heat generation were discussed in details. Apart from photothermal evaporation based clean water production, utilisation for photo-thermoelectric generation, photothermal catalysis, photothermal bacterial killing and phototherapeutic use were also included. Overall, the discussion in this chapter covers diverse categories of synthesis approach; schemes for high-efficiency photothermal device development; the challenges and opportunities anticipated in the future to make graphene based photothermal framework a perfect epitome of sustainable water treatment and power generation application.