Preparation of Thin-Layered Hexagonal Boron Nitride Nanosheet with Oxygen Doping.

Hexagonal boron nitride nanosheet (h-BNNS), a structural analogue of graphene, possesses remarkable properties such as exceptional electrical insulation, great resistance to corrosion, excellent mechanical strength, and thermal conductivity. Nonetheless, its continued development is still hampered by the lack of a preparation technique with an easy-to-follow procedure and reliable composition and structure control. In this study, we investigated a two-step protocol for uniform size production of thin-layered h-BNNS. By carefully manipulating the crystallization degree during synthesis of h-BN powder and employing subsequent hydrothermal treatment, we successfully obtained h-BNNS with an even thickness of only a few atomic layers. Compared with the broadly used liquid-phase exfoliation process, not only is the thickness significantly decreased but also the yield is considerably elevated to several grams. Moreover, the in-plane O doping content can be adjusted within a relatively wide range. Overall, our finding demonstrates the potential of this approach in facilitating the exploration and utilization of h-BNNS.