Enhanced Superhydrophobic Performance of BN-MoS2 Heterostructure Prepared via a Rapid, One-Pot Supercritical Fluid Processing.

Fabrication of highly crystalline BN-MoS2 heterostructure with >95% yield was demonstrated using one-pot supercritical fluid processing within 30 min. The existence of 20-50 layers of BN-MoS2 in the prepared heterostructure was confirmed by AFM analysis. The HR-TEM imaging and mapping analysis revealed the well-melded BN and MoS2 nanosheets in the heterostructure. The drastic reduction in XRD line intensities corresponding to the (002) plane and broadening of the peaks for the BN system over MoS2 indicated the effective exfoliation and lateral size reduction in BN nanosheets during SCF processing. Also, the exfoliated MoS2 nanosheets are preferentially exposed rather than BN nanosheets; consequently, the MoS2 nanosheets sturdily covered BN nanosheets in the heterostructure. The exfoliated BN and MoS2 nanosheets with nanoscale roughness make the surface highly hydrophobic in nature. As a result, the BN-MoS2 heterostructure showed superior superhydrophobic performance with high water contact angle of 165.9°, which is much higher than the value reported in the literature.