Scalable production of boron nitride nanosheets in ionic liquids by shear-assisted thermal treatment

Due to their intriguing properties, boron nitride nanosheets (BNNSs) with large lateral size and high crystallinity have great promise for many applications. However, the quantitative exfoliation of hexagonal boron nitride (h-BN) into good quality BNNSs still remains a key challenge. Herein, we report a scalable method to exfoliate BNNSs in ionic liquids (ILs) via shear-assisted thermal treatment. Few-layer BNNSs with well-preserved structural integrity are successfully prepared by this method. The synergistic effects of strong physical adsorption and intercalation of IL molecules, chemical interactions between hydrogen fluoride (HF) and h-BN, activation energy provided by heat treatment, and shear forces generated by repetitive stirring effect contribute to the exfoliation of BNNSs.

Automated summary

This study reports a scalable method to exfoliate boron nitride nanosheets in ionic liquids via shear-assisted thermal treatment, successfully preparing few-layer BNNSs with well-preserved structural integrity. The synergistic effects of physical adsorption, intercalation of IL molecules, chemical interactions between HF and h-BN, activation energy from heat treatment, and shear forces from stirring contribute to the exfoliation of BNNSs.