Design Synthesis and Excellent Anticorrosion Properties of ZIF-8/ZnMoO₄ Heterojunction Nanomaterials

This study enhanced the corrosion protection of zinc molybdate (ZnMoO4) in epoxy coatings by integrating ZIF-8 to form a Z-type nano heterojunction. The heterojunction leveraged the light absorption properties of organic ligands within ZIF-8 to significantly promote the excitation and separation efficiency of photogenerated carriers, thereby enhancing the photocathodic protection capability of the coating. It also utilized a cocrosslinking curing process between the epoxy functional groups and the organic functional groups of ZIF-8, resulting in a notable improvement in coating density. Furthermore, the metal–organic framework (MOF) effectively anchored the coating, preventing the recurrence of defects due to molybdate dissolution, thus enhancing durability. In synergy with the molybdate passivation film, it effectively hindered the corrosive attack of ions adsorbed on the metal substrate surface, thereby contributing to the suppression of chemical corrosion. Meanwhile, the compositing of MOF significantly enhanced the hydrophobicity of the material. Experimental data demonstrated that the impedance of the ZIF-8/ZnMoO4 composite coating achieved a remarkable increase to 226.0 and 208.3% compared to pure epoxy and ZnMoO4 coatings, which provided insights into expanding the compatibility and synergistic protective performance of molybdate-based corrosion-resistant materials by constructing heterojunctions between organic and inorganic materials.