Mussel-inspired facile fabrication of dense hexagonal boron nitride nanosheet-based coatings for anticorrosion and antifriction applications

Although great progress has been made recently in the research of hexagonal boron nitride ( h -BN) nanosheets, their practical applications are limited due to the difficulties of processability. Existing methods to modify h -BN usually suffer from tedious steps and chemical oxidation reaction conditions, which are being phased out owing to human health and environmental concerns. Herein, inspired by the mussel, dopamine is selected to functionalize h -BN (polydopamine-functionalized hexagonal boron nitride [ h -BN@PDA]) nanosheets which can improve interfacial compatibility thus enhancing their processability. As expected, dense h -BN@PDA nanosheet-based coatings can be fabricated through a facile environmentally friendly spraying process in the assistance of polyvinyl alcohol (PVA). The as-obtained coatings present excellent thermal stability because of the hydrogen bonds formed between h -BN@PDA and PVA. Additionally, suitable PVA is beneficial for load transfer, thus improving the mechanical properties of the coatings. More importantly, the composite coatings show good anticorrosion and antifriction performance since the h -BN@PDA nanosheets can act as physical barrier to corrosive medium and oxygen, or be stored in the worn surface as lubricant to reduce the friction and strengthen the friction stability. The facile fabrication process combined with the good thermal stability, anticorrosion and antifriction properties makes the h -BN@PDA nanosheet-based coatings promising candidates for practical applications. • Hexagonal boron nitride ( h -BN) nanosheet-based coatings can be easily fabricated using an environmentally friendly spraying technology just only with water as solvent. • The as-obtained coatings own substrate independence and remarkable capability for anticorrosion and antifriction. • MALDI) mass spectrometry imaging technology is applied to accurately characterize the distribution of polydopamine-functionalized hexagonal boron nitride ( h -BN@PDA), in which its accuracy is as high as ∼0.01%.