Preparation and Corrosion Resistance of Epoxy Coating Mixed by ZnO Hollow Microcontainer Containing Rhodamine B Hydrazide

ZnO hollow microspheres (ZHM) were synthesized by hydrothermal method. The ZHM containing rhodamine B hydrazide (ZHM-RHBH) was obtained by loading RHBH to ZHM using impregnation method, and characterized by Fourier transform infrared spectroscopy (FT-IR). A functional coating was prepared on Q235 carbon steel substrate by adding ZnO-RHBH into the epoxy resin. The effect of ZHM-RHBH on metal corrosion at coating defects was studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). It was found that the corrosion occurring at coating defects was inhibited by doping ZHM-RHBH into epoxy coating, and the ZHM-RHBH not only had certain healing effect for coating defects, but also could diagnose corrosion by fluorescence response.