Photocathodic protection has evoked great attention in stainless steel protection; however, it has not been fully studied on carbon steel. This study has prepared a series of TiO2/Zn3In2S6 nanocomposite films by combining anodic oxidation with hydrothermal methods, in which composition and morphology together with optical properties have been characterized. This heterojunction TiO2/Zn3In2S6 has allowed access to visible-light absorbance. Photoelectrochemical tests suggest that this film can supply effective photocathodic protection to carbon steel. The maximum photogenerated potential drop achieved on TiO2/Zn3In2S6-30 coupled to carbon steel is about −0.49 V even after 80 h of illumination, and the corresponding photocurrent is 1.91 mA·cm–2, which is about 5 times higher than that of pure TiO2. This is benefited from the effective photogenerated charge separation by the built-in electric field in the heterojunction. The detailed mechanism has been discussed in the paper.
A novel coating system of epoxy matrix containing aniline trimer modified silica conversion layer was prepared on Q235 steel surface. The conversion layer was obtained by electrodeposition on the basis of precursor solution, which contained ethyl silicate and modificatory aniline trimer (MAT). Hydrophobicity, electroactivity and corrosion resistance of as-prepared coating systems were detected. Result showed that the as-prepared MAT-including silica conversion layer (M-SiO2) presented a super-hydrophobicity and excellent electroactivity. Meanwhile, the novel coating system displayed a stronger adhesion force compared with single epoxy coating and silica/epoxy coating system. By electrochemical impedance spectrum and salt spray test, the protective capability of epoxy matrix was largely improved by the coverage of electroactive M-SiO2 conversion layer. This was attributed to the forceful hydrophobicity and self-healing ability of conversion layer. The synergistic effect of above-mention two functions promoted the perfection of corrosion performance for as-prepared novel coating system.
危险品化学品经营许可证（带存储）