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

Mussel-Inspired Interfacial Modification for Ultra-Stable MoS2 Lubricating Films with Improved Tribological Behavior on Nano-Textured ZnO Surfaces Using the AACVD Method

“…In addition, the S 2p spectrum (Figure 8f) contains two peaks at 162.0 and 163.2 eV corresponding to S 2p 3/2 and S 2p 1/2 , respectively. 22 The results indicate that the PDA interfacemodified sample can form a stable transfer film by chemical adsorption under high loads, thus improving the antifriction and anti-wear effect of the materials.…”

“…MoS 2 , a typical two-dimensional (2D) layered transition-metal dichalcogenide, has been widely used as a solid lubricant in the aviation field because of the excellent vacuum lubrication performance induced by its high interlayer anisotropy. − However, MoS 2 tends to be oxidized by oxygen and water vapor in the atmospheric environment, which reduces the friction properties and shortens the wear life. , Research has shown that metal doping − is a simple and economical method to improve the mechanical and tribological properties of MoS 2 solid lubricating materials. Meanwhile, the construction of micro-/nanotexture surfaces can not only improve the bearing capacity as power bearings but can also increase the storage capacity of lubricating materials and prolong the service life. − On the other hand, the poor adhesion between MoS 2 and a matrix has always been a perplexing problem. − Inspired by mussel adhesion proteins, polydopamine (PDA) formed by self-polymerization of dopamine is a polymer with outstanding adsorption performances, which can be adsorbed on various materials through strong covalent and non-covalent bonds to serve as an effective protective layer for nanostructures. − In particular, the rich functional groups (e.g., −NH 2 , −OH and catechol groups) on the surface of PDA have strong chelating ability for transition-metal ions (e.g., Zn 2+ , Fe 3+ , and Mo 4+ ), − which is beneficial to provide a reaction platform as a nucleation site to form a unique solid core–shell structure, thus improving the adhesion and load-bearing capacity of the film.…”

Friction Behavior and Structural Evolution of Hexagonal Boron Nitride: A Relation to Environmental Molecules Containing −OH Functional Group

“…h -BN is an insulator with a wide band gap (∼6 eV) that can serve as a dielectric substrate for graphene, MoS 2 , and other 2D nanomaterials. , Taking advantage of the electrically insulating characteristics, h -BN can also be used to fabricate an anticorrosion coating to alleviate the galvanic corrosion issues associated with graphene coatings. − In addition, h -BN holds remarkable potential for thermal management and mechanical reinforcements, which is an ideal candidate for reinforcing polymer matrix composites. It has been demonstrated that the h -BN nanosheet possesses a high in-plane thermal conductivity (1700–2000 W m –1 K –1 in theory and 1000 W m –1 K –1 in experiment) and a large Young’s modulus (∼1 TPa). − h -BN nanosheets can also be used in ceramic and metal matrix composites due to their impressive thermal stability, not experiencing oxidation in air until temperatures greater than 900 °C. , Particularly, h -BN can be considered as one of the green solid lubricants owing to its atomically smooth surface and easy shear capability that can effectively reduce friction. − Intrinsically, the unoccupied interlayer states present in the lower portion of the h -BN conduction bands, just as they are found in graphite, implying that the interlayer adhesion and shear strength may be as low as it could be. , As a result, by virtue of its high mechanical strength, thermal conductivity, oxidation, and corrosion resistance, the lubrication of h -BN would be exerted to the extreme.…”

Robust Transparent Titanium Dioxide Coating Based on the AACVD Process for Anticorrosion Marine Exploration

“…The total corrosion resistance (R total ) of the sample is evaluated by calculating the sum of R c and R ct . 39,40 It is known from the fitting results that the R total value of T-3 is 1.39 × 10 5 , which is about 2 orders of magnitude higher than that of T-2 (5.41 × 10 3 ) and T-1 (4.23 × 10 3 ), indicating that the denser T-3 sample possesses optimal barrier ability to improve the anticorrosion performance. Figure 6c shows that the impedance values of all samples deposited with TiO 2 coatings are higher than that of bare S420 steel.…”

“…The corrosion state can be judged more specifically by the equivalent circuit in the inset of Figure b, where R s , R c , R ct , Q c , and C dl are the resistance of the corrosion solution, the resistance of TiO 2 coating, the charge transfer resistance, the capacitance of TiO 2 coating, and the double-layer capacitance, respectively. The total corrosion resistance ( R total ) of the sample is evaluated by calculating the sum of R c and R ct . , It is known from the fitting results that the R total value of T-3 is 1.39 × 10 5 , which is about 2 orders of magnitude higher than that of T-2 (5.41 × 10 3 ) and T-1 (4.23 × 10 3 ), indicating that the denser T-3 sample possesses optimal barrier ability to improve the anticorrosion performance. Figure c shows that the impedance values of all samples deposited with TiO 2 coatings are higher than that of bare S420 steel.…”