Scalable Exfoliation and High-Efficiency Separation Membrane of Boron Nitride Nanosheets

Hexagonal boron nitride nanosheets (h-BNNSs) refer to a class of two-dimensional materials with promising applications. However, the current method of exfoliating hexagonal boron nitride (h-BN) into h-BNNS limits its large-scale application. Herein, a method was developed to exfoliate h-BN through sucrose assisted discontinuous, multiple ball milling. A series of defect-free, ultra-thin large lateral-size h-BNNSs were successfully obtained, with a yield as high as 85 wt %. Finally, the membranes of BNNS obtained by vacuum filtration displayed a good separation performance in different organic pigment solutions. The separation rates of BNNS-20 membranes for methylene blue and Congo red reached 87 % and 95 %, respectively. The results show that the functionalized h-BNNSs obtained by sucrose-assisted discontinuation, multiple ball milling have good stability in water, and hence can be applied to wastewater treatment