2D MoS2-hBN hybrid coatings for enhanced corrosion resistance of solid lubricant coatings

Molybdenum disulphide (MoS 2 ) is commonly utilized as a solid lubricant due to its outstanding wear resistance properties. However, the application of MoS 2 is restricted due to its high tendency of oxidation and corrosion when exposed to oxygen and humid air. Here, in this work, we developed a 2D hybrid structure by incorporating the 2D material , hexagonal boron nitride (hBN), with MoS 2 to enhance the corrosion resistance properties. MoS 2 -hBN 2D hybrid coatings with varying concentrations of hBN nanosheets were deposited onto mild steel specimens to evaluate tribological and corrosion properties. The friction studies were carried out using a high-frequency reciprocating tribometer (HFRR) and found that hybrid coatings showed a slightly higher coefficient of friction (CoF) than pure MoS 2 coating due to hBN addition. Electrochemical corrosion studies of the coatings were conducted in 3.5 wt% NaCl solution. Potentiodynamic polarization and electrochemical impedance spectroscopy studies depicted lower corrosion rate and higher corrosion resistance for MoS 2 -hBN coatings than pure MoS 2 coating. The increase in hBN content resulted in an enhanced corrosion resistance. Raman spectroscopy studies of corroded coatings revealed the presence of a high concentration of MoO 3 in pure MoS 2 coating, while oxide peaks were nearly absent in MoS 2 -hBN coatings. XPS analysis depicted comparatively lower oxidation and MoO 3 concentration in hybrid coating compared to pure MoS 2 coating. • MoS 2 -hBN 2D hybrid coating prepared on mild steel • Addition of hBN does not significantly alter the anti-friction properties of MoS 2 • With increase in hBN content, the corrosion resistance of the coating increases • hBN prevents the oxidation of MoS 2 due to strong interlayer coupling