Ultrathin BN nanosheets with zigzag edge: one-step chemical synthesis, applications in wastewater treatment and preparation of highly thermal-conductive BN–polymer composites

Ultrathin BN nanosheets (BNNSs) were prepared at 300 °C by a new variable-pressure one-step chemical synthesis route. It was found that the thickness of BNNSs decreased from 8 nm to 3 nm with the pressure increasing from 10 MPa to 90 MPa, and all the BNNSs are triangular in shape with a zigzag edge. These BNNSs have high specific surface area, and thus exhibit high adsorption capacities for the organic dye methylene blue (MB). The maximum specific surface area and adsorption capacity of BNNSs are 182 m2 g−1 and 436 mg g−1, respectively. Besides, the BNNSs can also be used as excellent thermal-conducting additives in BN–polymer (Nylon66 and polyvinyl alcohol (PVA)) composites. Especially, the thermal conductivity of BN–PVA film can be improved up to 3.44 times with only 3 wt% of BNNSs.