Simple fabrication of superhydrophobic carbon felt with outstanding Joule heating and photothermal effects for all-weather recovery of viscous crude oil

The development of materials with simple preparation methods and exhibiting excellent photothermal and Joule heating effects, especially at low safety voltage inputs for reaching desired temperatures, is of great significance for realizing all-weather rapid recovery of high viscosity crude oil, but some challenges currently exist. Herein, carbon felt (CF), known for its excellent electrical properties, was used as a substrate and coated with molybdenum disulfide (MoS2) with excellent electrical properties and light absorption ability through a one-step hydrothermal method. Subsequently, the surface energy of the felt was reduced by further surface modification using polydimethylsiloxane (PDMS) to prepare superhydrophobic and superoleophilic CF (PDMS@MoS2@CF). It exhibited significant photothermal effects and exceptional Joule heating capabilities at safe low voltages, benefiting from the excellent electrical properties of CF and the exceptional photothermal and electrical properties of MoS2. Under 1 sun irradiation or a 2 V voltage, the surface temperature of PDMS@MoS2@CF could reach up to ∼78.5 °C or 93.0 °C, respectively. In addition to achieving low viscosity oil recovery, this material rapidly generated heat due to photothermal and Joule heating effects, significantly reducing the viscosity of crude oil and effectively achieving crude oil recovery. Further, the continuous recovery of crude oil from water surface could be realized using a peristaltic pump. Furthermore, the two effects complemented each other, enabling the all-weather rapid recovery of high viscosity crude oil while maximizing resource conservation and thus showing practicability. This material shows application prospects in addressing oil spills, particularly in scenarios involving high viscosity crude oil.