Self-Assembled ZnO QDs@ZIF-8 Fillers for Low-Cost Bronze Artifacts Corrosion Monitoring

Abstract

Self-warning coatings are functional materials capable of converting subtle microscopic corrosion signals into macroscopically detectable optical responses; however, the high cost of conventional fillers and the complexity of core–shell fabrication hinder their large-scale application. To address this, we developed a composite material based on self-assembled ZnO quantum dots@ZIF-8 (ZnO QDs@ZIF-8) for low-cost corrosion monitoring of bronze artifacts. The material was synthesized via ultrasound-assisted preparation of ZnO quantum dots, followed by one-step encapsulation with ZIF-8 using 2-methylimidazole, resulting in a uniform core–shell structure. This process is simple and efficient (completed within 1 h at a cost of $0.05 per gram), and the resulting composite enables highly sensitive detection of Cu²⁺ through a fluorescence quenching mechanism (LOD = 78 nM). When integrated into an acrylic coating, the material can convert invisible corrosion signals into visible optical changes, achieving self-warning of corrosion. This offers a scalable solution for cultural heritage preservation and holds potential for extension to industrial monitoring systems.