High-Quality Boron Nitride Nanosheets and Its Bioinspired Thermally Conductive Papers

• Published in: ACS applied materials & interfaces 2019-09
• Main Authors: Zhao, Hongran, Ding, Jiheng, Shao, Zhen-Zong, Xu, Beiyu, Zhou, Qing-Bo, Yu, Haibin
• Format: Article
• Language: English
• ISSN: 1944-8252

Hexagonal boron nitride (hBN) has displayed increased potentials in heat dissipation applications due to its desirable high thermal conductivity and remarkable thermal stability. However, the large-yield and high-quality preparation of boron nitride nanosheets (BNNSs) has been still an enormous challenge. In present work, we developed a universal exfoliation strategy to synthesize few-layer and defect-free BNNSs, which involved the intercalation of hexafluorosilicates/sodium hydroxide into BN crystals, followed exfoliation through a mild stirring process. The yield and concentration of as-obtained BNNS reached up to 78.5% and 12.78 mg/mL, respectively. More importantly, this method has been proved to exfoliate other layered materials like graphene (G), MoS2, and WS2. These as-obtained BNNSs can be directly used for constructing freestanding papers with a highly thermal conductivity. Typically, the thermal conductivities of the BNNS-G hybrid paper were up to 63.5 W/mK along the in-plane direction and 7.4 W/mK along the through-plane direction, respectively. According to the thermal interface materials (TIMs) performance measures, BNNS-G hybrid paper shows great promising applications for heat transfer in integrated circuit packaging.