Corrosion Study of Boron Nitride Nanosheets Deposited on Copper Metal by Electrophoretic Deposition

Abstract

Two-dimensional nanomaterials, such as graphene, boron nitride nanosheets (BNNS), molybedenum disulphide nanosheets, have been extensively researched for various applications. Corrosion protection of metals with the help of coatings is also one of the areas where the potential of these nanomaterials has been explored. Recent reports showed graphene-based coatings can improve corrosion resistance of metals in the sea environment. This study aims to evaluate corrosion protection ability of BNNS deposited on Copper (Cu) metal. BNNSs were developed from boron nitride particles by ultrasonicating them in isopropanol for 8 h followed by separation using centrifuge. The supernatant, colloidal solution of BNNS/isopropanol, obtained by centrifugation was mixed with few drops of reduced graphene oxide/water suspension to achieve BNNS deposition by electrophoretic deposition, which employed Cu metal as cathode and platinum as anode. The as-developed BNNS coatings on Cu were characterized for their morphology, functionality, composition and structure using scanning electron microscope, Fourier transform infrared and Raman spectroscopy, energy dispersive x-ray analysis and x-ray diffraction, respectively. The corrosion behavior of coatings was studied by Tafel analysis, electrochemical impedance spectroscopy (EIS) and cyclic voltammetery in 3.5% NaCl solution. Tafel analysis showed that BNNS coatings improved corrosion resistance of Cu metal by five times. EIS analysis showed high impedance and capacitive behavior of BNNS coatings.