Advances in Solar Interfacial Evaporation Technology: Device Structural Design Toward Efficient Freshwater Collection

With the escalating global water crisis, solar interfacial evaporation technology has emerged as a vital, green, and efficient solution to freshwater scarcity in recent years. While current studies on solar interfacial evaporation are predominantly centered on photothermal conversion materials—significantly enhancing evaporation rates—the ultimate objective of such systems remains the effective collection of freshwater. This constitutes a critical issue that cannot be overlooked in practical applications. Enhancement of the vapor collection rate (VCR) can be achieved through several avenues: 1) structural innovations in evaporation components that elevate the water evaporation rate; 2) optimization of condensation structures to improve condensation efficiency; and 3) integration of thermal storage mechanisms, such as encapsulating phase change materials, to extend operational duration. This review categorizes and summarizes recent advancements in solar interfacial evaporation devices specifically designed to augment the VCR, with emphasis on analyzing their structural configurations. The aim is to provide both theoretical foundations and practical references for developing novel vapor collection systems, while offering research directions and inspiration for future investigations.