Electrochemical preparation and corrosion resistance of ZIF coating on carbon steel surface
Renjun Luo, Jihui Wang, Wenbin HuPurpose
This study aims to fabricate an efficient hydrophobic anticorrosion coating in situ on Q235 steel by combining electrodeposition with hydrophobic surface modification, and to clarify its corrosion protection mechanism.
Design/methodology/approach
Zeolitic imidazolate framework (ZIF)-90 coatings were electrodeposited on Q235 steel and subsequently modified with octadecylamine (ODA) to obtain hydrophobic ODA-ZIF-90 coatings. The morphology and structure of the coatings were characterized by scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy, while the hydrophobicity was evaluated by water contact angle measurements. The corrosion resistance was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and immersion tests in NaCl solution.
Findings
The as-prepared ODA-ZIF-90 coating significantly enhanced the corrosion resistance of Q235 steel and exhibited a water contact angle above 140°. EIS results showed that the impedance value reached 1.38 × 109O·cm2. Potentiodynamic polarization measurements indicated that the corrosion current density decreased markedly, with an inhibition efficiency of 99%. After immersion in 3.5 Wt.% NaCl solution for 14 days, the corrosion protection efficiency remained above 91%. However, after 21 days of immersion, the impedance value decreased significantly, indicating severe coating degradation and loss of effective protection.
Practical implications
This study develops a simple, cost-effective and efficient method to in-situ fabricate hydrophobic corrosion-resistant coatings on carbon steel via electrodeposition. The prepared ODA-ZIF-90 coating significantly enhances the corrosion resistance of Q235 steel, while greatly reducing the preparation time compared with conventional anticorrosion coating methods. In addition, the multifunctionality of metal-organic framework (MOF) materials provides abundant modification possibilities, enabling the design of coatings with different functional properties according to specific application requirements. This work offers a promising strategy for the rapid preparation of high-performance MOF anticorrosion coatings.
Originality/value
This study proposes a simple and effective strategy for constructing corrosion-resistant coatings on carbon steel surfaces through electrodeposition combined with hydrophobic surface modification of a MOF. It provides a feasible route for the economical, efficient and rapid fabrication of MOF-based anticorrosion coatings, thereby effectively improving the corrosion resistance of Q235 steel.