Photothermal Shape-Memory Nanofibrous Membrane for Efficient Recovery of High-Viscosity Crude Oil

Efficient recovery of highly viscous crude oil remains a critical challenge due to the poor mobility and slow diffusion of such oils under ambient conditions. Here, a photothermal shape-memory nanofibrous membrane (CB@AUA/SIS) was developed via the electrospinning of aliphatic polyurethane acrylate (AUA) and polystyrene-block-polyisoprene-block-polystyrene (SIS), incorporating carbon black (CB) as a low-cost photothermal filler. The electrospun architecture provides a high surface area and porosity, while the CB endows the membrane with light absorption (reaching 98%) and a high photothermal conversion efficiency of 73.4%. Upon irradiation, the membrane rapidly heats to 61.2 °C, effectively reducing the viscosity of crude oil. Together with the intrinsic lipophilicity of the AUA/SIS copolymer, a high adsorption rate of 6240 g·m–2·min–1 is achieved. In addition, the membrane exhibits excellent hydrophobicity and a light-responsive shape memory effect. This allows the folded structure to autonomously unfold on water surfaces, facilitating its intelligent deployment. Outdoor sunlight tests further confirm its reliable performance. This work demonstrates a multifunctional, light-adaptive system that integrates solar-driven heating and programmable shape transformation for the remediation of viscous crude oil spills.