Nanoengineered t-ZrO₂ coatings for superior corrosion resistance on steel surfaces

Corrosion of steel has several catastrophic consequences in various sectors. The inorganic nanoparticle-based anticorrosive coating on steel drew important attention to its large surface-to-volume ratio. The primary aim of this study is to synthesize and characterize t-ZrO₂ nanoparticles at an optimized annealing temperature and evaluate their structural, morphological, and optical properties. Additionally, the study investigates their effectiveness as a corrosion inhibitor for carbon steel in 1 M H₂SO₄. The study explores the cheap, facile, green synthesis of t-ZrO₂ nanoparticles (NPs) through bark extract from the gum arabic plant (Acacia nilotica) for anticorrosive coatings on carbon steel. X-ray diffraction (XRD) analysis confirms the tetragonal phase structure and the crystallite size, calculated using Scherrer's formula, is found to be 8.1 nm. Fourier-transform infrared (FT-IR) spectroscopy reveals the presence of Zr-O bonding along with organic residues from plant extracts, confirming the formation of t-ZrO₂ NPs. Field emission scanning electron microscopy (FESEM) images confirm a rock stone-like structure, while energy dispersive X-ray (EDX) spectroscopy verifies the presence of Zr and O elements. The study further investigates the corrosion inhibition efficiency of t-ZrO₂ NPs on carbon steel in 1 M H₂SO₄. The atomic force microscopy (AFM) analyses reveal a smoother surface with reduced roughness in the presence of the inhibitor. Electrochemical measurements, including weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS), confirm a significant reduction in corrosion rate. The inhibition efficiency reaches 95.2% at 200 ppm of 0.2 M t-ZrO₂ NPs, with an increased charge transfer resistance (R_ct) of 14,715 Ω cm² and a reduced double-layer capacitance (C_dl) of 0.631 × 10⁸ F/cm². These findings demonstrate that t-ZrO₂ NPs act as an effective corrosion inhibitor for carbon steel in acidic environments.