Abstract:

This paper systematically reviews the thermodynamic and kinetic theoretical framework for solar-driven evaporation processes, aiming to provide a systematic theoretical foundation for this multiscale, multiphysics-coupled photo-thermal evaporation phenomenon. First, from a thermodynamic perspective, it elaborates on the phase equilibrium conditions, free energy structure, and phase diagram representations involved in evaporation, covering vaporliquid phase equilibrium descriptions for both single-component fluids and multicomponent mixtures. Second, from a kinetic viewpoint, the analysis focuses on pathways to break vaporliquid phase equilibrium: one involves driving evaporation by altering the thermodynamic state of the gas phase (e.g., pressure reduction); another involves driving evaporation by modifying the thermodynamic state of the liquid phase (e.g., localized interfacial heating), which is the core mechanism of photothermal evaporation; and the third introduces kinetic theories based on gas- or liquid-phase diffusion combined with moving boundary conditions under a simplified diffusion-dominated framework. Furthermore, the paper integrates experimental studies on photothermal evaporation to examine the influence of geometric constraints-particularly nanoconfinement effects-on evaporation behavior and energy transport pathways, and reviews engineering application strategies and performance evaluation methods in confined systems, such as two-dimensional water pathways and porous structures. Finally, it outlines current theoretical bottlenecks and future research directions. By integrating thermodynamic equilibrium analysis with kinetic evolution mechanisms, this paper attempts to offer theoretical insights for understanding and designing efficient and stable solar-driven evaporation systems.

Key words: solar-driven evaporation, thermodynamics, kinetics, phase equilibrium, liquidvapor phase transition, nanoconfinemen