Corsican stonecrop structured superoleophilic melamine sponge for oil–water separation, enhanced photothermal cleanup of viscous oil spills and photocatalytic activity

Superwetting materials, particularly superhydrophobic absorption materials have garnered extensive attention for their role in addressing oil spills. Despite this, creating a durable and multitasking superhydrophobic absorbent for efficient oil–water separation and rapid clean-up of highly viscous crude oil remains challenging. In this study, we developed a superhydrophobic melamine sponge (MS/CuO/DDT) with special wettability properties by growing CuO and coating 1-dodecanethiol on the melamine sponge via a hydrothermal method. The results demonstrated that the prepared superhydrophobic sponge evinced a water contact angle of 151° and an oil contact angle of 0° in air, indicating its superhydrophobicity and superoleophilicity. The MS/CuO/DDT showed a high oil absorption capacity (84–183 g/g), resilient recyclability (>40 cycles), unparalleled separation efficiency for oil-in-water emulsions (>99 %), good mechanical stability, excellent photothermal performance for managing viscous oil spills, and high photodegradation ability. These characteristics make MS/CuO/DDT highly suitable for cross-functional oil–water separation in complex environments.