Constructing small‐sized oriented pores and an ultrathin photothermal conversion layer to boost solar‐driven interfacial evaporation

Abstract Acquiring freshwater from seawater, the solar interfacial vapor generator (SIVG) offers a passive and decentralized approach to addressing water shortage problems. However, the performance of current SIVGs is greatly restricted by the disadvantages of poor controllability and manipulation of seawater transport porous structure and the evaporation interface. To realize rapid seawater replenishment and highly efficient vaporization, we developed a novel polyethylene terephthalate (PET) SIVG with small‐sized oriented pores and an ultrathin photothermal conversion layer that exhibited a highly efficient water evaporation rate under both simulated solar and outdoor sunlight illumination. The well‐arranged and highly oriented pores with controllable size in PET acted as a confined mass transfer fluid pump to spontaneously transport seawater to the evaporation layer, in which a maximum height of 68 mm via the capillary rise mechanism was reached. The resultant PET layer possessed a low density of 0.08 g cm −3 that exhibited an ideal floating performance to steady the interfacial evaporation. Moreover, due to the superior dispersion structure in the photothermal conversion layer, the surface temperature of the SIVG greatly increased to 101.2 °C within 45 s, and the evaporation rate reached 1.26 kg m −2 h −1 . This work provides a novel strategy for preparing a high performance SIVG and also paves an innovative way for obtaining fresh water. © 2025 Society of Chemical Industry.