Surface engineering strategies for realizing hexagonal boron nitride composite coatings for corrosion protection

Abstract During the past decades, graphene has been confirmed as an excellent corrosion barrier due to its superior impermeability. However, it fails to achieve the long-term metallic protection because the highly-conductive graphene could accelerate the electrochemical degradation of substrates. Hexagonal boron nitride (hBN) nanosheets (BNNSs) have been considered as the most promising substitute based on its intrinsic insulation, superior chemical and thermal stability. The development of superior BN-based composite coatings (BNCCs) has attracted a great deal of attention, aiming to realize high-performance anticorrosion coating materials, and numerous efforts have been made in surface engineering and basic fabrication of BNCCs. In this paper, we provided a critical review on statues, advances, and challenges in surface engineering and fabrication of BNCCs in corrosion protection. The processing-structure-property relationships between functionalized BNNSs and BNCCs were in-depth discussed. Finally, the research perspectives of BNCCs were proposed. With this review, we hope to instigate the novel ideas and functionalization strategies for the preparation of high-performance BNCCs in future.