Synthesis and characterization of layer-by-layer assembled magnesium zinc molybdate nanocontainer for anticorrosive application

• Synthesis of magnesium zinc molybdate nanoparticles for core of nanocontainers.
• Dual corrosion inhibition mechanism with combination of magnesium, zinc and molybdate.
• Loading of benzotriazole inhibitor using LbL technique resulting in a nanocontainers.
• Enhancement in anticorrosive performance due to inorganic core.
• Significant improvement in the anticorrosive performance of nanocontainers.

Magnesium zinc molybdate nanoparticles which has been synthesised by conventional method, used as core of nanocontainer. In the present work, a novel approach for the loading and responsive release of corrosion inhibitor (benzotriazole) on the magnesium zinc molybdate nanocontainer by layer by layer (LbL) assembly has been presented. The synthesized nano particle coated with corrosion inhibitor i.e. benzotriazole and polyelectrolyte layer, provides enhanced corrosion protection. The thickness of the layer, surface charge and functional groups present on each layer has been achieved by using particle size distribution (PSD), zeta potential and Fourier transform infrared spectroscopy (FTIR) analysis respectively. The X-ray diffractograms (XRD) and thermogravimetric analysis (TGA) gives the development of nanoparticle as well as nanocontainer. The morphological studies shows the variation in the size of magnesium zinc molybdate nanoparticles and the nanocontainer. The release of benzotriazole from the magnesium zinc molybdate nanocontainer has been quantitatively evaluated in water at different pH. The anticorrosive performance of nanocontainers has been studied by incorporating it in epoxy based coating and evaluating by DC polarization measurement. The current density has been found to be decrease significantly with the addition of 1 wt.% of magnesium zinc molybdate nanocontainers in neat epoxy-polyamide resin. Additionally, corrosion potential values are shifted to positive side with the addition of 1 wt.% of magnesium zinc molybdate nanocontainers. The corrosion results from Bode plots and Salt spray test shows the significant improvement in anticorrosive performance for epoxy-polyamide-nanocontainer coatings. The results shows the successful application of magnesium zinc molybdate nanoparticles as a core of nanocontainers by giving rise to dual corrosion inhibition mechanism due to combination of magnesium, zinc, molybdate ions and inhibitor loaded on inorganic core.