Novel carbon based membrane for enhanced interfacial photothermal vaporization

This is a 2-year Royal Society - International Exchanges 2022 Round 3 funded project starting from 31st March 2023.

Solar thermal systems are one of the direct approaches to solar energy harvesting. One implementation of this technology is related to solar-driven vapour generation (SDVG) systems, where the vapor is generated at lower temperatures compared to boiling points. SDVG systems not only play a present role in driving diverse industrial applications such as power generation and steam sterilization but they have been used and proposed to address the global water shortage problem. Traditional solutions such as reverse osmosis and
multistage flash are not feasible for remote locations, mainly because of their high energy consumption and expensive infrastructure installation. Solar-driven vapour generation is considered one of the promising approaches, which eliminate these challenges. However, solar-driven vapour generation systems have low efficiency due to water’s poor optical absorption and heat losses to the ambient.

The proposed research involves an interdisciplinary investigation, which proposes a novel and functional 3D architectural carbon-based hybrid structures for solar-driven vapour generation systems. The functional photothermal material consisting of two separate, yet unified layers will be synthesized to be used for
supplying the required capillary flow rate for photothermal evaporation. The top layer structure - consisting of carbon fibres – not only augments the light trapping but also remarkably increases the evaporation and vapour
generation capacity of the system. The bottom layer – consisting of foam-like graphene – increases the capillary pumping and enhances surface wetting for sufficient water supply. Such a functional structure will remarkably enhance the energy efficiency, salt repellency, and scalability of the proposed project.