Sustainable corrosion resistance of piroxicam-cyclodextrin inclusion complex to mild steel and its mechanism

Abstract

Finding new cost-effective and environmentally friendly anti-corrosion materials is a never-ending task. Herein, the main objective is to prepare a new formulation based on piroxicam-cyclodextrin inclusion complex (PX@β-CD) as an efficient green inhibitor to protect mild steel against corrosion in 1 M HCl. The inhibition performance of PX@β-CD was determined by electrochemical tests coupled with theoretical study like as DFT calculation to assess the reactivity and interaction mechanisms between PX@β-CD and Fe. The obtained results revealed that PX@β-CD performs excellently inhibition performance where its inhibition efficiency reached 98.65% at 0.4 mM, and it acted as a mixed type inhibitor with anodic predominance. SEM and contact angle analysis showed the formation of compact PX@β-CD film on steel surface. The adsorption of PX@β-CD inhibitor followed the Langmuir adsorption model according to the gravimetric corrosion measurement. Thermodynamic analysis and DFT calculations revealed the chemisorption of the inhibitors on the steel surface.

Keywords

• Piroxicam-cyclodextrin
• Corrosion protection
• Inclusion
• DFT calculation