Bio-inspired synthesis of highly crystallized hexagonal boron nitride nanosheets

Abstract Boron nitride nanosheets (BNNSs) exhibit great potential as a two-dimensional dielectric material due to superior thermal and chemical stability. However, compared with mature processing techniques for graphene, mass production of BNNSs mainly depends on mechanical exfoliation routes until now, which do not control the morphology and crystallinity of the products. In this study, we demonstrate a biomass-inspired strategy for synthesizing highly crystalline and purified hexagonal BNNSs using ambient pressure chemical vapor deposition. Using Bellamya quadrate shells as both the catalyst and template not only led to a reliable, non-toxic, and low-cost synthetic route, but also used food waste as raw material. The BNNSs produced were characterized to be atomically flat, with few layers, a single crystalline hexagonal morphology, and with a classic band gap of 6.05 eV. In addition, the BNNSs could be utilized as fillers to fabricate thermoplastic polyurethane composites, presenting a 3.6 time and 3.7 time increase in thermal conductivity and elastic modulus than pure thermoplastic polyurethanes, respectively.