Photothermal materials exhibit significant potential for marine applications, yet their efficiency and durability require enhancement. This study presents a dual-layer photothermal device that integrates a polyurethane light absorption layer with a wood sponge layer, designed for water transport and thermal insulation. The wood sponge’s hydrophilicity and effective water transport properties improve water supply while minimizing heat loss. Under sunlight, the device achieves a surface temperature of 63.2°C and an evaporation rate of 1.86 kg/m2/h for seawater desalination. The porous design of both layers ensures salt resistance during extended desalination processes. Furthermore, the incorporation of disulfide bonds into the polyurethane enhances the material’s self-healing properties, enabling sustained performance even after prolonged use, thus extending its service life. Additionally, the device demonstrates effective crude oil adsorption capabilities attributed to its photothermal efficiency and porosity. This innovative design provides valuable insights for advancing solar-driven evaporation devices and crude oil adsorption systems in marine environments.