Bioinspired Design of Textile-Based Absorbers: Photothermal and Electrothermal Synergistic Conversion for Efficient Clean-Up of Heavy Oil

It is a worldwide challenge to achieve an efficient cleaning of heavy oil at ambient temperature. Conventional cleanup methods for high-viscosity oil spills exhibit low absorption efficiency and have severe practical operating limits. Herein, inspired by the passive transport process in the Salvinia cucullata, a solar-heated and joule-heated textile-based absorber using the scalable electrostatic flocking technique. Benefiting from the efficient photothermal and electrothermal conversion effects, the textile-based absorber, with oleophilic and aligned channels, facilitates thermal conduction and hence enhances heavy oil absorption. The absorber is highly efficient for organic solvents (chloroform and dichloromethane) and low-viscosity oils (silicone oil, gasoline, and diesel oil). The surface temperature of the textile absorber rises rapidly to 92 °C (114 °C) in 120 s (240 s) under one sun irradiation (or 5 V voltage), resulting in a sharp drop in the viscosity of the heavy oil and then achieving an ultrahigh absorption rate (2647 kg h⁻¹ m⁻²) and fast equilibrium time (25 s). Rapid absorption rate significantly reduces spill cleanup time and spill spreading area, hence alleviating the environmental harm caused by oil spills as much as possible. The proposed solar-heated and joule-heated textile-based absorbers with aligned channels show great potential for efficient heavy oil absorption.

Graphical Abstract