Electrochemical approach to interfacial adsorption and inhibitory performance of (2E)-2- [(IH-Imidazole 2yl) methylidene] Hydrazine1-carbothioamide for corrosion mitigation

This work features the synthesis and use of (2E)-2- [(IH-Imidazole 2yl) methylidene] Hydrazine1-carbothioamide (IMHC) as anticorrosion agent for mild steel (MS)corrosion in 0.5 M sulfuric acid (H₂SO₄). Electrochemical studies were conducted at different temperatures. Conditions were optimized to achieve maximum inhibition efficiency. Kinetic parameters were evaluated. Results were fitted into various adsorption isotherms. Thermodynamic parameters were calculated by using suitable equations and graph. The surface morphology study was done by scanning electron microscope (SEM) and energy dispersive X-beam (EDX). The inhibition efficiency was found to decrease with rise in temperature. Maximum percentage inhibition efficiency (%IE) observed was around 79 with 1 × 10⁻³ M IMHC at 303 K. IMHC functioned as mixed inhibitor. Results obtained suggested that physical adsorption of IMHC occurred onto the MS surface and obeyed Langmuir model. Mechanism is discussed in detail. IMHC can be considered as good inhibitor for corrosion of MS in H₂SO₄ medium.