Foam-Based Hybrid Photothermal Hydrogels with High Evaporation Efficiency

Long-term and efficient seawater desalination using hydrogel-based solar photothermal evaporators relies on two critical factors: high photothermal conversion efficiency and effective salt resistance. In this study, we developed a sustainable, environmentally friendly, and cost-effective foam-based hydrogel solar interfacial evaporator incorporating inorganic telluriumselenium (Te-Se) nano-heterojunctions with outstanding photothermal performance. The foam hydrogel facilitates water activation and enables rapid absorption and supply, ensuring a consistent water replenishment during the evaporation process. Concurrently, the TeSe nano-heterojunctions function as the photothermal component, leveraging their exceptional solar absorption and photothermal conversion properties. The synergistic interaction between these components results in an evaporation rate of $3.63 \mathrm{~kg} \mathrm{~m}^{-2} \mathrm{~h}^{-1}$ under one-sun illumination, with an energy efficiency exceeding 90%. This performance highlights the significant potential of this approach for practical applications in seawater desalination.