Novel inorganic solid controlled-release inhibitor for Q235-b anticorrosion treatment in 1 M HCl

Abstract Borate was regarded as an interesting material for a broad range of applications. Here, we had prepared a novel borate-based controlled-release inhibitor to improve the anticorrosion performance of Q235-b in 1 M HCl. The effective components released by the inhibitor were boron and sodium, and its anticorrosion performance was investigated by various electrochemical methods The potentiodynamic polarization curve results indicated that the borate-based inhibitor showed a clear anodic-type inhibitor characteristic, and a great improvement of the resistance was obtained from the electrochemical impedance spectroscopy, resulting from the formation of a passive film with Fe O B structure on the Q235-b surface. The formation process followed the Langmuir isotherm well, and the passive film showed a self-healing capability, which confirmed by the electrochemical noise. Further, the anticorrosion capability of the inhibitor gradually increased with the increasing release time. After 21 days of release, the boron concentration reached 125 mg L −1 , the anticorrosion efficiency was over 97%, and a smooth surface was observed on the Q235-b surface from electron microscopy. According to these results, we believed that the borate-based controlled-release inhibitor displayed a satisfactory capability to suppress corrosion on the Q235-b surface in 1 M HCl. The present work provided a novel concept for the development of corrosion inhibitor.