Preparation and separation performance of biomimetic polycaprolactone/graphene oxide composite membrane

The treatment of oil and water pollutants generated in industrial production and daily life is an urgent issue that needs to be addressed globally. Inspired by superhydrophobic self-cleaning lotus leaves, durable and sturdy superhydrophobic water-filled barriers, and lightweight bird bones with hollow structures, researchers can obtain superhydrophobic surfaces by creating rough surfaces of layered micro- and nanostructures. In this study, hydrophobic polycaprolactone (PCL) membranes with layered structures were prepared by electrospinning. The surface roughness of the PCL membrane was improved by compounding graphene oxide (GO) functional components on the PCL membrane surface, thereby enhancing its hydrophobicity. The infrared spectrum of the PCL/GO membrane shows that PCL and GO are physically mixed, and no chemical changes occur during the electrospinning process. Scanning electron microscopy (SEM) images of the composite fibre membranes reveal the interconnections between fibres. Fourier transform infrared spectroscopy (FTIR) provides information on the chemical components of the membranes. Thermogravimetric analysis (TGA) was employed to assess the thermal stability of the membranes. The oil-water separation test demonstrated that the PCL/GO membrane exhibited a separation efficiency of 99.94% for hexane-water mixtures. In the oil adsorption test, the maximum adsorption capacity of the membrane for n-hexane was 35.8 g/g. In the contact angle measurement experiment, the water contact angle of the nanofiber membrane increased from 120.12° to 140.15° with increasing GO content, indicating that the composite membrane exhibited enhanced hydrophobicity.