In-situ exfoliation of large sized h-BNNS by esterified nanocellulose to build aqueous lubricants that can switch between liquid and gel states

The development of cellulose-based aqueous dispersions provides new ideas for the preparation of green lubricants. Herein, an esterified cellulose-assisted in-situ exfoliation (ECAIE) method was used to produce large lateral sized 2D materials in cellulose dispersions which with excellent dispersion stability. Taking h-BN as an example, the ECAIE method produces NC@h-BNNS aqueous dispersion with lateral size of h-BNNS reaching 1200 nm, exhibiting excellent lubrication properties. The obtained aqueous lubricants show the ability to switch between liquid (oscillation) and gel (resting) states. This method was also extended to the production of aqueous dispersions of various other cellulose/2D materials, and the efficient lubrication of the resulting dispersions on engineered steel surfaces has been demonstrated, indicating their great potential in the field of lubrication.