Hexagonal boron nitride (hBN) is a valuable polymorphic material that has been exploited by various market segments for decades, forming the basis of cosmetic products as early as 1940. Large-scale commercialization of hBN products lagged until the ‘90s when synthesis and production processes were optimized to meet growing global demand. The material was revolutionized yet again following the discovery of graphene in 2004, when mechanical exfoliation demonstrated how to generate atomically-thin materials in real-world conditions.
Bulk hBN is structurally analogous to graphite. It follows, therefore, that single-layer hBN is reminiscent of graphene. These two materials have followed a similar development trajectory since the actualization of two-dimensional (2D) materials research just 15 years ago. It is now possible to generate single-layer hBN via bottom-up methods like chemical and physical vapor deposition (CVD/PVD), on a choice of substrate materials. This has yielded extremely positive results in terms of electronic, mechanical, and optical properties.
Electronic Properties of hBN
Single-layer hBN is a superb dielectric material that has been used in the electronics sector as a thermal regulation material for years. While the in-plane dielectric strength of hBN exceeds that of refractory alumina (Al2O3), single-layer hBN films also exhibit high proton conductivity at room temperatures. This unique permeability is of particular interest in hydrogen fuel cell research.
Mechanical Properties of hBN
Although significant characterization of single-layer hBN has been carried out to show that it is the strongest electrical insulation 2D material currently available, comparatively little research has explored the material’s mechanical properties. Studies have shown that atomically thin hBN exhibits improved retention of strength with increasing layers compared to graphene, the strength of which decreases by over 30% from a single layer to a stack of eight graphene films. This is attributed to interlayer reactions which may be linked to the inherent lubricity of hBN products.
Optical Properties of hBN
Single-layer hBN has a bandgap of approximately 5.97 electron-volts (eV), which is responsible for the bulk materials white coloring. Research into the optical properties of hBN has also yielded extremely positive results with respect to the material’s potential nanophotonic properties. This corresponds with hBN’s limited sensitivity to temperature changes, particularly with regards to its bandgap.
hBN Products from Grolltex
Grolltex is one of the leading suppliers of single-layer hBN grown via CVD and transferred on to a choice of substrates. We offer a range of products at the highest possible quality control standards. If you would like to learn more, read our previous blog post Outlining the hBN Products from Grolltex.
Otherwise, contact a member of the Grolltex team today with any questions.
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