Micron-scale ultrathin two-dimension zirconia nanosheets towards enhancing anticorrosion performance of epoxy coatings

Polymer nanocomposite coatings have attracted great interest in the anticorrosion fields due to their excellent properties. Nanofillers are necessary to achieve high anticorrosion performance of the polymer coating. Herein, we report a wet-chemical template strategy to prepare large-size ZrO 2 nanosheets, in which the Zr 4+ ions are anchored on the surface of a graphene oxide template via electrostatic adsorption, followed by a thermal treatment process to remove graphene. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) images show that the size and thickness of as-prepared ZrO 2 nanosheets are more than 2 μm and ~ 4.5 nm, respectively. The micron-scale ultrathin two-dimension (2D) ZrO 2 nanosheets, for the first time, are utilized as the anticorrosive fillers in the epoxy coating to reduce the porosity, consequently promoting the gas and water barrier properties of the composite coating. The polymer coating containing 1.0 wt% ZrO 2 nanosheets shows a high initial impedance (89.1 GΩ·cm 2 ) that can protect the metal substrate from being corroded during long-term immersion (60 days), which is better than that of the reduced graphene oxide (rGO)-incorporated coating and the ZrO 2 nanoparticles-incorporated coating. This work offers valuable insights into the design and preparation of novel and efficient 2D electric-inert nanofillers for anticorrosion coatings.