Photothermal materials with broad solar absorption and high conversion efficiency have recently attracted significant interest. They are becoming a fast-growing research focus in the area of solar-driven vaporization for clean water production. The parallel development of thermal management strategies through both material and system designs has further improved the overall efficiency of solar vaporization. Collectively, this green solar-driven water vaporization technology has regained attention as a sustainable solution for water scarcity. In this review, we will report the recent progress in solar absorber material design based on various photothermal conversion mechanisms, evaluate the prerequisites in terms of optical, thermal and wetting properties for efficient solar-driven water vaporization, classify the systems based on different photothermal evaporation configurations and discuss other correlated applications in the areas of desalination, water purification and energy generation. This article aims to provide a comprehensive review on the current development in efficient photothermal evaporation, and suggest directions to further enhance its overall efficiency through the judicious choice of materials and system designs, while synchronously capitalizing waste energy to realize concurrent clean water and energy production.

Solar absorber material and system designs for photothermal water vaporization towards clean water and energy production

Solar energy is a major source of renewable energy with the potential to meet the energy demand and to support the sustainable development of the world. The efficient harvesting and conversion of solar energy is one of the key factors to maximize the utilization of solar energy. In general, solar energy can be harnessed and converted into various kinds of energy, including electricity, fuels and thermal energy, through photovoltaic, photochemical and photothermal processes, respectively. Among these technologies, photothermal conversion is a direct conversion process that has attained the highest achievable conversion efficiency. The photothermal effect has been used as a novel strategy to augment vaporization and catalysis performance. In this review, we look into the basis of the photothermal conversion process, the design of efficient photothermal conversion materials in terms of both light harvesting and thermal management, a fundamental understanding of various system schemes, and the recent progress in photothermal evaporation and catalysis applications. This review aims to afford researchers with a better understanding of the photothermal effect and provide a guide for the rational design and development of highly efficient photothermal materials in energy and environmental fields.

Solar-driven photothermal nanostructured materials designs and prerequisites for evaporation and catalysis applications

Steam generation in a nanoparticle-based solar receiver

Surface plasmon resonance (SPR)-induced photothermal heating has garnered a substantial amount of research interest across various disciplines. The first applications of SPR-induced light-to-heat energy conversion were in biological systems to photothermally ablate cancer cells in vivo. More recently, this spatially localized and highly tunable heating technique has been extensively used for a variety of chemical reactions and other associated applications. This feature article highlights the recent developments in surface plasmon-mediated photothermal chemistry. We review the current theoretical and experimental work toward estimating the photothermal heating-induced surface temperatures of plasmonic nanostructures. From a mechanistic perspective, we show how this local heating can activate reactant molecules and boost numerous types of chemical reactions. We also discuss the physical changes occurring in a surrounding solvent, such as water, during the photothermal process. Finally, we extend the scope ...

Surface Plasmon-Mediated Photothermal Chemistry

Volumetric solar heating and steam generation via gold nanofluids

Heat transfer from nanoparticles to a surrounding liquid pool is an essential process for many applications. This work investigates the heat transfer process upon a continuous wave laser heating to a gold nanoparticle (GNP) in a water pool through molecular dynamics (MD) simulations based on realistic potentials. The interactions among gold atoms are described by the embedded atom method (EAM) potentials, both the rigid and flexible TIP3P water models are examined, and a modified Lennard-Jones potential is used for the interaction between the GNP and water. The results show that the interfacial thermal conductance is influenced by the selection of different water models and the interfacial wettability. The interfacial thermal conductance is smaller but increases slightly with the increase of heat flux for the flexible water model, while it keeps almost constant for the rigid model. Increasing the wettability between the particle and the fluid reduces the interfacial resistance. The rise of the interfacial...

Xiaoling Chen

Papers

Molecular Dynamics Simulation of Heat Transfer from a Gold Nanoparticle to a Water Pool