Functionalization of hexagonal boron nitride in large scale by a low-temperature oxidation route

A simple and effective method to functionalize hexagonal boron nitride (hBN) was demonstrated by low temperature (600 °C) oxidation of hBN powders in air. An oxygen-rich amorphous layer was observed on the surface of oxidized hBN particles. Compared to raw hBN, the oxidized hBN particles showed better affinity with ethanol. In addition, the oxidation process and mechanism were also investigated in detail. The results showed that the longer oxidation time, the thicker oxidation coating would be formed. In the beginning of oxidation, oxygen could insert into the lattice ascribe to the surface defects of hBN. With oxidation time increasing, more oxygen would embed in the inner of h-BN particles, causing the intense lattice distortion in local zone. With the oxidation process proceeded, the amorphization behavior would appear, and form a coating of amorphous boron oxides on the surfaces of h-BN particles. This method holds great promise for the application of hBN materials.