Self-Healing Properties of Tannic Acid-Functionalized ZIF-8/Reduced Graphene Oxide Nanocomposites for Corrosion Protection

Abstract

The evolution of composite materials has progressed from basic natural mixtures to advanced engineered systems, fueled by the continuous pursuit of enhanced mechanical strength and durability. A pivotal paradigm shift within this domain is "self-healing" technology a biomimetic approach empowering materials to autonomously detect and repair micro-cracks, thereby mitigating catastrophic failure. While conventional polymeric composites often rely on extrinsic microcapsules, recent research prioritizes "smart" nanocontainers for active corrosion control. Such as, Metal-Organic Frameworks (MOFs) have emerged as state-of-the-art reservoirs due to their high specific surface area and stimuli- responsive release capabilities (Atighi et al., 2025; Lee et al., 2015). Especially, their integration with Reduced Graphene Oxide (rGO) enhances the coating's tortuosity and impermeability (Atighi et al., 2025). In addition, some studies proved that Tannic Acid (TA) can serve as a dual-functional green inhibitor and supramolecular cross-linker. So that, we have envisioned to produce a novel TA functionalized Zeolitic imidazolate frameworks (ZIF-8) /rGO composites and investigate their self- healing properties as anti-corrosive protectors. ZIF-8 nanoparticles were synthesized via a facile aqueous room-temperature precipitation method. Following it, rGO was produced from graphite sources using the Hummers' method (Emiru & Ayele, 2017). The active interface was engineered by functionalizing the ZIF-8/rGO nanohybrids with TA through a functionalization-assisted etching process. The chemical functionalization were rigorously characterized using Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, and UV-Vis Spectroscopy. To evaluate the smart self- healing and stimuli-responsive performance, a pH-dependent release test was conducted in different media and monitored via UV-Vis Spectroscopy. These analyses confirmed the successful synthesis of the nanocomposites, with crystallographic phases and spectral bands showing high concordance, thereby validating the purity and stability of the produced nanocontainers.