Artificial ‘nacre-like’ architectures assembled using ice templating/freeze-drying from two-dimensional boron nitride and graphene oxide layers

The need for thermal management in microelectronics, polymer composites with high performing thermo-physical properties have drawn significant attention. However, the traditional method by random addition of nanofillers usually create composites with limited thermal conductivity and require large threshold loading of fillers leading to detrimental effects. To this end, we report fabrication of artificial nacre-like (‘mother of pearl’) aerogels and paper-thin films based on noncovalent functionalized boron nitride (BNNS) and graphene oxide (GO) nanosheets by ice-templating self-assembly combined with freeze-drying. The electron microscopy images showed ‘brick-and-mortar’ type arrangement in BNNS and GO nanosheets which are chemically bridged with long-chain PVA molecules via hydrogen bonds. Novel polymer composites are prepared by constructing a three-dimensional BNNS (3D-BNNS (and 3D-GO) topological network followed by infiltration with thermally stable D.E.R.32 epoxy matrix. Thermomechanical properties elucidated higher glass transition temperature and low interfacial thermal resistance (or high thermal conductivity) with lower loading revealing their superiority.