Non-covalently functionalized boron nitride mediated by a highly self-assembled supramolecular polymer

A new method for exfoliation of hexagonal boron nitride (h-BN) into few-layered nanosheets has been developed by employing noncovalent assembly of networks upon association with a supramolecular polymer. In this work, we developed a simple, reliable, effective approach for preparation of exfoliated h-BN nanosheets from bulk h-BN via liquid-phase exfoliation using a low-molecular weight adenine-functionalized polypropylene glycol (A-PPG) supramolecular polymer. A-PPG self-assembled into either long-range ordered lamellar or micelle-like structures on the surface of h-BN because of the strong specific interactions between A-PPG and h-BN. The level of h-BN nanosheet exfoliation could be controlled by adjusting the amount of A-PPG incorporated. This newly developed composite exhibited excellent phase transition behavior and thermal stability, and few-layer thickness with good dispersion of h-BN nanosheets, indicating self-assembled A-PPG functions as an efficient dispersant and stabilizer to manipulate the physical and morphological properties of exfoliated h-BN. This method of producing multifunctional exfoliated h-BN provides a unique paradigm for developing the next generation of thermoconductive devices and solution-processed semiconductors.