In-situ bonding technology and excellent anticorrosion activity of graphene oxide / hydroxyapatite nanocomposite pigment

Abstract

Abstract The design synthesis of new anticorrosive pigments for reducing disasters and energy consumption is of great significance. Here, graphene oxide-hydroxyapatite (GO-HAP) nanocomposite with stable structure is fabricated via in-situ bonding technology. The interlaced structure of GO-HAP nanocomposite protects the steel substrate from attack by the corrosive species. Moreover, the free aggressive Cl− ions can be immobilized by the replacement with the hydroxyl groups in HAP crystal to generate stable chlorapatite, further defending the steel substrate from destruction. In addition, the electrons released from the anode can be collected by GO sheets for inhibiting the cathodic reaction. Thus, the GO-HAP nanocomposite, as an anticorrosion pigment, exhibits a remarkable anticorrosion performance. In comparison with blank epoxy resin system, the impedance value of 0.6% GO-HAP/epoxy increases by 754.4%. The synergistic complementation mechanism of GO and HAP enriches metallic anticorrosion theory and provides a new thought for synthesis of novel and promising anticorrosive pigments.