Optical absorber-assisted thermal evaporation can enable a variety of innovative renewable energy applications, ranging from water purification to chemical fractionation. Many of these applications can catalyze new industries and hence drive global economic growth. For example, the ability to use solar energy for fresh water production will tackle many challenges in the water-energy nexus. The present project is motivated by a recently observed liquid evaporation using highly localized heating effect from functionalized light absorbing nanoparticles. In such a demonstration, water vapor was generated while the bulk temperature remained at about 30 degrees C. The underlying physics is not yet understood, and the mechanism is related to the convoluted multi-phase (liquid-vapor-solid) thermal and mass transport, which needs this multi-disciplinary study to unlock. The fundamental thermal transport science to be gained from this project is expected to guide the development of new technologies to utilize solar energy, resulting in significant broader impacts on applications. This project will enable the education and training of graduate students and undergraduate students from under-represented groups in the universities.
This project is driven by the hypothesis that enhanced interfacial thermal transport and the self-assembled monolayer defect-assisted nucleation combine to enhance bubble generation and improve the overall evaporation effect. To test this hypothesis, the objectives of this proposal are to (1) understand the fundamental relationship between the surface functionalization, thermal transport and the subsequently mass transport in bubble dynamics through a combination of molecular simulations and mesoscale hydrodynamics modeling; and (2) validate such a relationship through experiments on vapor generation around photo-excited functionalized nanoparticles. This project will employ a combination of molecular simulation, mesoscale modeling and experimental validation to achieve a multi-scale understanding of this fundamental problem with unprecedented resolution.
