Exfoliation of MoS 2 and h-BN nanosheets by hydrolysis of LiBH 4 .

Efficient preparation of two-dimensional materials is still a great challenge. These materials possess unique electrical, optical, and thermal properties. In this study, few-layer MoS2 nanosheets and nanoflakes were exfoliated by the hydrolysis reaction of LiBH4 . First, the layered MoS2 powder materials were mixed with LiBH4 to obtain a homogeneous powder mixture, and then the mixture was heated above the melting point of LiBH4 under 300 °C and 4 MPa H2 for 2 h, during which the layered materials were curled by liquid LiBH4 . In the subsequent hydrolysis of LiBH4 , the layered materials were split into nanosheets by H2 gas generation. The obtained MoS2 nanosheets show almost uniform thickness of ~4 nm, with a width of 2-10 μm and a yield of more than 1.5 wt.%. The effectiveness of this method has also been verified by the preparation of few-layer h-BN. This work provides a new high-yield route to producing two-dimensional materials.