Elastic‐Photothermal Graphene‐Modified Super‐Wetting Sponge for Efficient Purification of Multicomponent Oil‐Water Emulsions

Abstract The extensive discharge of oily wastewater has caused significant harm to global ecosystems and human health. While super‐wetting materials offer a promising low‐energy solution for oily wastewater separation and purification, current technologies suffer from inefficient pore structure control and poor separation performance for high‐viscous oil phases in multicomponent emulsions. Here, an elastic photothermal graphene‐modified sponge is presented, fabricated via a “Swell‐Shrink” impregnation strategy, enabling strain‐responsive tuning of pore structure and purification flux (15–450 L m ⁻² h ⁻¹ ). The system exhibits outstanding purification performance across multiple pollutant categories, with 99.9% dye removal, 99.8% emulsion separation, and overall efficiency exceeding 98.6%. Moreover, the photothermal effect facilitates the rapid migration of the high‐viscous oil phase in emulsions, overcoming transport limitations and achieving 99.2% separation efficiency. Compared with existing super‐wetting materials, this material has significant advantages in terms of overall performance. As proof‐of‐concept, it is proven that the treated filtrate from high‐load oily waste emulsions meets Chinese standards for agricultural irrigation and exhibits biocompatibility comparable to pure water. Moreover, the filtrate from toxic industrial dye wastewater also supported normal zebrafish embryo development. This work introduces a dynamic water treatment system that combines photothermal and strain‐responsive mechanisms, providing a scalable solution for intelligent wastewater purification and sustainable ecological remediation.