Experimental and Theoretical Study of Piper Nigrum Seed: Isolation of Piperine, DFT/MD Adsorption Modeling and Nano-formulation as a Green Corrosion Inhibitor for Carbon Steel in 1.0 M HCl

Abduliridha, Suror W.; Farhadi, K .; Sabzi, Reza E.; Abdulnabi, A.S

doi:10.22034/abec.2025.733513

Experimental and Theoretical Study of Piper Nigrum Seed: Isolation of Piperine, DFT/MD Adsorption Modeling and Nano-formulation as a Green Corrosion Inhibitor for Carbon Steel in 1.0 M HCl

Document Type : Original Article

Authors

Suror w. Abduliridha ¹

K . Farhadi ¹

Reza E. Sabzi ¹

A.S Abdulnabi ²

¹ Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran

² Department of Chemistry, College of Education for Pure Sciences, University of Basrah, Basrah, Iraq

10.22034/abec.2025.733513

Abstract

This study presents an integrated experimental and theoretical investigation into the corrosion inhibition of carbon steel in 1.0 M HCl using Piper nigrum seed extract and its poly(lactic-co-glycolic acid) or PLGA-based nanoformulation. Electrochemical analyses revealed that the nanoencapsulated system markedly suppressed anodic dissolution and cathodic hydrogen evolution, achieving inhibition efficiencies above 90% across a wide concentration range. Surface characterization via SEM, TEM, EDS, and FTIR confirmed the formation of a compact, adherent protective layer, with distinct shifts in C=O, C–O, and aromatic vibrational bands evidencing chemisorption of phytochemicals and polymer-assisted encapsulation. Complementary density functional theory (DFT) calculations and molecular dynamics (MD) simulations demonstrated strong electron donation, favorable adsorption geometry, and stable inhibitor–metal interactions with adsorption energies exceeding −170 kJ/mol. The combined findings establish a robust mechanistic basis for the inhibitor’s performance, highlighting the synergistic benefits of phytochemical constituents and nanocarrier encapsulation. The results not only underscore the promise of Piper nigrum as an eco-friendly corrosion inhibitor but also demonstrate how nanoengineering strategies can advance green chemistry approaches to industrial corrosion mitigation.

Keywords

Piper nigrum extract

Poly(lactic-co-glycolic acid) nanoformulation

Green corrosion inhibitor

Electrochemical impedance spectroscopy

Potentiodynamic polarization

Density functional theory

Molecular dynamics simulation

Sustainable corrosion mitigation

Subjects