Zn Wetted CeO₂ Based Composite Galvanization: An Effective Route To Combat Biofouling

Area of Science:

• Materials Science
• Corrosion Engineering
• Marine Biology

Background:

• Microbial-induced corrosion (MIC) poses a significant threat to steel infrastructure in marine environments.
• Existing protective coatings often lack sufficient long-term efficacy against persistent microbial biofilms.
• Developing advanced materials with synergistic properties is crucial for enhanced corrosion and biofouling resistance.

Purpose of the Study:

• To develop and characterize a novel Zn-wetted CeO2 (Zn/CeO2) composite galvanic zinc coating.
• To evaluate the anticorrosion and antibiofouling performance of the developed coating against MIC.
• To elucidate the mechanism behind the enhanced antibiofouling activity.

Main Methods:

• Fabrication of Zn/CeO2 composite galvanic coatings with controlled Zn and Ce content.
• Electrochemical impedance spectroscopy (EIS) to assess corrosion resistance.
• Antifouling assays using cultured marine microbial consortia.
• Surface analysis techniques to study bacterial attachment and biofilm formation.

Main Results:

• The Zn/CeO2 composite coating demonstrated significantly enhanced antibiofouling activity.
• Optimized coatings (28 wt% Zn, 34 wt% Ce) exhibited high charge transfer resistance (4.0 × 10^14 Ω cm^2) and low capacitance.
• Significant reduction in bacterial attachment and biofilm formation was observed.
• The antibiofouling mechanism involves Ce reduction and oxidation state shuttling, impairing bacterial respiration.

Conclusions:

• The novel Zn/CeO2 composite galvanic coating is highly effective in combating MIC.
• The synergistic effect of Zn and Ce provides excellent stability and corrosion resistance.
• This coating offers a promising solution for protecting steel equipment in corrosive marine environments.