Development of ecofriendly high performance anti-corrosive chitosan nanocomposite material for mild steel corrosion in acid medium

The present study discusses preparation, characterisation and corrosion inhibition of mild steel exposed to acidic medium (1M HCl using) nanocomposite based chitosan (CH) doped with zinc oxide nanoparticles ZnO NPs. Preparation of CH-ZnONPs was carried out via facile, in situ reduction, coast effective and green method. The characterisations of the synthesised inhibitor CH-ZnONPs were evaluated using FTIR, XRD, SEM-EDX, TEM, TGA, DLS and N-2 adsorption-desorption as well as the antimicrobial activity. Results showed that CH-ZnONPs was prepared in nanoscale (26-136 nm) with surface area more than neat CH by about ten folding. Moreover, The DLS measurement results were configured high stability of the CH-ZnONPs. CH-ZnONPs was assessed as a potential corrosion inhibitor for mild steel in acid solutions 1M HCl. Experimental evaluations were carried out at various concentrations to investigate the inhibition efficiency and adsorption behaviour of CH-ZnO NPs. Electrochemical and surface investigations were used to investigate the efficiency of in inhibiting corrosion (SEM-EDX and surface roughness). The results indicated that increasing the concentration of the green corrosion inhibitor CH-ZnO NPs increased the efficiency of the used inhibitor, which reached 93.95% in the presence of 100 ppm. Furthermore, the CH-ZnO NPs functioned as a mixed-type corrosion inhibitor, according to Tafel extrapolated polarisation measurements. The Nyquist plot of impedance is mostly represented by a depressed capacitive loop with various concentrations of inhibitor. The CH-ZnONPs inhibit metallic corrosion by means of an adsorption mechanism adopting the isothermal model of Langmuir adsorption. Surface morphology examinations, in addition to electrochemical tests, result in a significant evidence for the existence of an inhibitor molecules adsorbed across the mild steel surface.

Automated summary

This study prepared CH-ZnONPs using a facile, in situ reduction, cost-effective and green method, showing high stability and nanoscale size. CH-ZnONPs functioned as a potential corrosion inhibitor for mild steel in 1M HCl acid solutions, with an inhibition efficiency reaching 93.95% at 100 ppm. The inhibitory mechanism involved adsorption on the mild steel surface, as evidenced by surface morphology examinations and electrochemical tests.