MOF-derived NiCo-LDH-BTA composite nanocontainers for anticorrosion and microwave-absorbing multifunctional coatings

In this work, a benzotriazole (BTA)-loaded (Metal Organic Framework) MOF derived NiCo (layered double hydroxide) LDH nanocontainer (ZLB) was developed and incorporated into a polyvinyl butyral (PVB) matrix to fabricate a multifunctional coating with integrated anticorrosion and Microwave absorption capabilities. The BTA loading capacity of ZLB reached 35 wt%. The encapsulated BTA exhibited pH-responsive release behavior, with accelerated liberation under both acidic and alkaline conditions. Such release characteristics ensure inhibitor storage stability during service while enabling stimulus-triggered protection once the local environment becomes corrosive. Electrochemical measurements confirmed that the incorporation of ZLB markedly improved the protective performance of the PVB coating. The coating exhibited a corrosion current density as low as 1.29 × 10 −8 A·cm −2 and a corrosion rate of 1.501 × 10 −4  mm·year −1 at an optimal filler content of 1.8 wt%. In addition, ZLB delivered a minimum reflection loss of −30.4 dB at 7.8 GHz with a matching thickness of 2.0 mm. These results demonstrate that the integration of ZIF-8, NiCo-LDH, and BTA creates a hierarchical interfacial structure and enhances inhibitor-mediated active protection in the PVB coating. Meanwhile, the ZLB filler exhibits microwave-attenuation capability, providing a promising strategy for designing thin anticorrosion coatings containing multifunctional nanofillers.