Corrosion protection of electrospun PVDF-ZnO superhydrophobic coating

A one-step electrospinning technique was used to prepare a protective superhydrophobic PVDF-ZnO nanocomposite coating for aluminum against corrosion. The wettability and morphology of the prepared coating surfaces was characterized using water contact angle and contact angle hysteresis measurements, scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy. In addition, the corrosion resistance for Al with PVDF polymer and the PVDF-ZnO nanocomposite coatings compared to the bare Al was investigated by electrochemical impedance spectroscopy and Tafel polarization techniques. The results showed that, the water contact angle and the contact angle hysteresis of the prepared PVDF-ZnO nanocomposite coating were 155 ± 2 and 4.5 ± 2°, respectively. In addition, compared to the sprayed PVDF-ZnO coating, the concentration of ZnO nanoparticles in the electrospun coating was only one sixth to obtain the same water contact angle, better distribution of ZnO nanoparticles was achieved without using any dispersing agent. The analysis of the corrosion results revealed that, the superhydrophobic PVDF-ZnO coating showed a corrosion protection efficiency for Al that is much higher than that of the PVDF one.