Conformal growth of B/N modified graphene on metal strings by chemical vapor deposition for robust protection

For string-plucked instruments, the metal strings are always subjected to sweating corrosion and ambient oxidation during the daily use. A specifically thin protection coating, which will not alter its timbre and tone, is highly desirable. In this study, a two-dimensional (2D) coating of B/N-modified graphene (BNG) films is proposed to deposit on the surface of Cu alloy strings via chemical vapor deposition (CVD) as a corrosion barrier. Through providing appropriate amount of B/N dopant, conformal growth of BNG films on Cu alloy string substrate with sharp step-terraces topography can be optimized, and largely improving its robust anti-corrosion performance in both short-term electrochemical tests and long-term ambient corrosion tests for evaluation. On one hand, the conformal coupling between in-situ grown BNG and Cu alloy string can form a strong interaction which limits the interfacial diffusion of corrosive species. On the other hand, once the defects oxidation is initialized, B/N modified graphene can reduce its conductivity, then suppressing the electrochemical corrosion in the long-term protection. With the insights and understanding of in-situ coating method and the enhanced anti-corrosion mechanisms, this work will extend the potential applications of 2D materials as an atomic-thick protective coating for some special devices and instruments.