A Review on Multi-Scale Structural Design of Graphene-based Photothermal Materials for Solar Interfacial Evaporation

With global water scarcity and environmental pollution becoming increasingly serious, solar interface evaporation technology has become a key path to solve the freshwater crisis due to its advantages such as renewability and zero carbon emissions. Owing to their broad-spectrum light absorption, graphene and its derivatives exhibit remarkable potential in photothermal conversion applications, high thermal conductivity, as well as readily tailored surface characteristics. However, a single component is difficult to meet the comprehensive needs including fast evaporation kinetics, resistance to salt crystal formation, and long-lasting structural reliability. Through multi-scale structural design such as macroscopic three-dimensional configuration (aerogel, hydrogel, membrane structure), microscopic pore engineering (graded pores, vertical orientation pores), and surface chemical modifications (affinity/hydrophobic modification, functional group introduction, and charge regulation), the synergistic regulation of light, heat and quality can be realized, and the evaporation efficiency and environmental adaptability can be significantly improved. The present review comprehensively discusses the structural design strategies and performance regulation mechanisms for graphene-derived photothermal materials, discusses the structure-activity relationship and the principle of multi-scale synergy, and aims to lay theoretical groundwork and supply technical references for high-performance solar interfacial evaporation material development.