Nano-to-Macroscale Insights into Solar Evaporation: Bridging Fundamental Principles to Intelligent Systems

Solar water evaporation has emerged as an alternative vapor generation strategy to address global water scarcity and reduce carbon emissions. Recent advances have achieved significant improvements in solar evaporation efficiency, driven by innovations in nanostructured materials, interfacial engineering, and system-level integration. This review presents nano-to-macro insights into solar evaporation by bridging physicochemical fundamentals with intelligent system design. An overview of the evolution of solar evaporation technologies is provided followed by a comprehensive discussion of the multiscale physicochemical principle processes involving energy conversion and flow, water activation and phase transition, water transport, and vapor diffusion. Subsequently, these principles are integrated into nano- and macroscale systems to enhance solar-to-thermal and thermal-to-vapor conversion, salt-rejecting fouling, and water collection performance. We also highlight the diverse applications of solar evaporation systems, including wastewater treatment, sustainable steam generation, advanced power systems, and catalytic integration. Importantly, the incorporation of artificial intelligence enables dynamic optimization, adaptive control, and predictive modeling, offering promising pathways for intelligent and scalable solar evaporators. Finally, we discuss ongoing challenges and future opportunities from molecular-level design to device engineering and large-scale implementation.