ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Electrochemical and DFT/MD simulation studies on expired temozolomide drug as an efficient corrosion inhibitor for mild steel in 1 M H₂SO₄

Harsh Rana, Akshita Tikoo, Harvinder Singh Sohal, Navneet Kaur, Manvinder Kaur, Mohd Rafatullah, Ankush Mehta, and Lalit Goswami

Materials and Natural Product Laboratory, Department of Chemistry, Chandigarh University, Gharuan, Mohali, India

E-mail: drharvinder.cu@gmail.com

Received: 21 February 2026  Accepted: 13 May 2026

Abstract:

Expired temozolomide (TZM) was evaluated as a corrosion inhibitor for mild steel (MS) in 1 M H₂SO₄ using gravimetric, electrochemical, surface, and theoretical studies. Corrosion rate decreased significantly with increasing TZM concentration (0–500 ppm), achieving maximum inhibition efficiencies of 98.90%, 92.45%, and 88.46% at 25, 45, and 65 °C, respectively. Electrochemical studies indicated TZM acts as a mixed-type inhibitor by forming a protective adsorbed layer on MS surface. Adsorption follows Temkin and Freundlich isotherms, suggesting heterogeneous, predominantly physisorption-driven interaction supported by negative Gibbs free energy values (-20 to -30 kJ/mol). Surface analysis (SEM, AFM, XPS, contact angle, UV) confirmed formation of a compact inhibitor film. DFT and molecular dynamics studies revealed strong interactions and stable adsorption of TZM on the Fe (110) surface. Overall, expired TZM is an efficient and eco-friendly corrosion inhibitor for acidic environments.

Keywords: Adsorption; Corrosion inhibition; DFT analysis; Expired temozolomide; MD simulation; Mild steel

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-05064-1

Chemical Papers 80 (9) 11099–11121 (2026)