Boron Nitride Nanosheets for Metal Protection

TL;DR

Boron nitride nanosheets serve as a thermally and chemically stable, electrically insulating barrier that effectively protects metals from oxidation and corrosion, outperforming graphene in long-term applications.

Contribution

This study demonstrates the potential of commercially available BN nanosheets as a superior protective coating for metals, highlighting their stability and corrosion resistance.

Findings

BN nanosheets significantly reduce copper oxidation at 250°C in air.

Electrochemical tests show increased potential and reduced oxidation of coated copper.

Protection effectiveness depends on the quality of BN nanosheets.

Abstract

Although the high impermeability of graphene makes it an excellent barrier to inhibit metal oxidation and corrosion, graphene can form a galvanic cell with the underlying metal that promotes corrosion of the metal in the long term. Boron nitride (BN) nanosheets which have a similar impermeability could be a better choice as protective barrier, because they are more thermally and chemically stable than graphene and, more importantly, do not cause galvanic corrosion due to their electrical insulation. In this study, the performance of commercially available BN nanosheets grown by chemical vapor deposition as a protective coating on metal has been investigated. The heating of the copper foil covered with the BN nanosheet at 250 {\deg}C in air over 100 h results in dramatically less oxidation than the bare copper foil heated for 2 h under the same conditions. The electrochemical analyses reveal that the BN nanosheet coating can increase open circuit potential and possibly reduce oxidation of the underlying copper foil in sodium chloride solution. These results indicate that BN nanosheets are a good candidate for oxidation and corrosion protection, although conductive atomic force microscopy analyses show that the effectiveness of the protection relies on the quality of BN nanosheets.