News Coatings Technologies
Unveiling the zinc precursor effect on ZIF-8/g-C₃N₄ epoxy coating performance
A new study demonstrates how zinc precursors influence the particle size and interfacial interaction of ZIF-8/g-C₃N₄ hybrids, optimising the corrosion protection performance of epoxy coatings.
The chemical nature of zinc precursors plays a crucial role in the crystallisation of metal-organic frameworks (MOFs) and their corrosion protection performance in composite coatings. Recent research explores how zinc precursors can strategically modify the particle size and interfacial chemistry of ZIF-8/g-C₃N₄ hybrids for epoxy coatings.
Four zinc precursors—nitrate, acetate, chloride, and gluconate—were studied, yielding ZIF-8 particles with distinct sizes and morphologies. Acetate-derived ZIF-8-C particles (∼400 nm, uniform rhombic dodecahedrons) displayed the strongest bonding interaction with g-C₃N₄, confirmed through FT-IR analysis and dispersion tests. Incorporated into epoxy matrices, these hybrids deliver exceptional barrier properties, maintaining a low-frequency impedance of 1.04 × 10⁸ Ω·cm² over 40 days—significantly outperforming other coatings.
Reading tip: Corrosion protection coatings
The book “Anticorrosive Coatings: Fundamentals and New Concepts” brings together all the disciplines involved in the creation and use of corrosion protection coatings for metals. It presents the latest insights into the quality and chemistry of surfaces, the proper way to prepare them by conversion treatment, the function of resins and anticorrosion pigments in paints, and novel concepts in corrosion protection. As an added bonus, all the standards and directives mentioned in the text are grouped together in their own chapter for a better overview.
Superior adhesion and corrosion protection
Additional tests confirmed the high performance of ZIF-8-C/epoxy coatings. After 300 hours of salt spray testing and adhesion measurements (3.863 MPa dry, 2.587 MPa wet), the coatings demonstrated excellent corrosion resistance and substrate bonding. These results stem from optimised particle size, enhanced dispersion, and strong interfacial bonding, which collectively block the diffusion pathways of corrosive agents and enable effective self-healing.
This study provides valuable insights into the “precursor-structure-performance” relationship, paving the way for the rational design of MOF-based composite coatings.
Source: Zhang, B. et al., Unveiling the zinc precursor effect: Interfacial interaction and particle size of ZIF-8/g-C₃N₄ hybrids dictating epoxy coating performance. Progress in Organic Coatings, 109897 (2025).
