The inhibition of mild steel corrosion in 3% HCl solution by sulfamethoxazole (SZ) and norfloxacin (NF) were investigated at 25 8C using weight loss measurement. The measurements reveal that the inhibition efficiency grows with increasing concentrations of inhibitors, and the inhibition efficiency decreases in the order NF > SZ. The adsorption of inhibitor molecule on mild steel surface follow Langmuir isotherm. Quantum chemical calculation was performed to correlate electronic structure parameters of SZ and NF with their inhibition performances. The molecular dynamics simulations were applied to find the equilibrium adsorption configurations and calculate the interaction energy between inhibitors and iron surface. The efficiency order of the studied inhibitors obtained by experimental results was verified by theoretical calculations.

Phytate had been investigated as a corrosion inhibitor for NdFeB magnets in an aqueous salt solution. Potentiodynamic polarisation, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and energy dispersive spectroscopy were employed for this investigation. The polarisation curves results revealed that phytate acted as a mixed type inhibitor. The inhibition efficiency was found to increase by maximum 96.5% through increasing the phytate concentration to 0.5 mM at 308C. The inhibition was proposed to result from the adsorption of phytate on NdFeB magnets, which was found to obey the Langmuir adsorption isotherm. The inhibition mechanism was explored by the potential of zero charge (E pzc ) measurement at the solution/metal interface.