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Scanning electron micrograph of c-BN nanocrystallites developed by researchers at North Carolina State University. Credit: Anagh Bhaumik; North Carolina State University diamond,” Narayan says in the release. “We have bypassed what were thought to be the limits of boron nitride’s thermodynamics with the help of kinetics and time control.” The team’s results suggest that Q-BN is even harder than diamond and may be useful for cutting tools. c-BN is a form of boron nitride that has a cubic crystalline structure comparable to diamond, the release explains, but c-BN ticks some boxes diamonds just cannot. Those include potential biomedical applications, a higher bandgap for higher-power electronics and solid-state devices, and effective transistors, because the material can be “doped” to give it positively and negatively charged layers. The material also forms an oxide layer on its surface when exposed to oxygen, making it stable at high temperatures and in oxygen-ambient environments and potentially useful as a protective coating for high-speed machining tools. And the new technique for creating c-BN is faster and less expensive than previous methods—which equals better scale-up potential. Creating c-BN used to require heating hexagonal boron nitride to 3,500 K (5,840°F) and applying 95,000 atm of pressure, the release explains. “Using this technique, we are able to create up to a 100- to 200-square-inch film of Q-BN or c-BN in one second,” Narayan says. Armed with their latest innovation, Narayan and his team have their sights set on the future with the goal to transform the way high-powered devices are constructed for better efficiency. “We’re optimistic that our discovery will be used to develop c-BN-based transistors and high-powered devices to replace bulky transformers and help create the next generation of the power grid,” Narayan says. The paper, published in APL Materials, is “Research update: Direct conversion of h-BN into pure c-BN at ambient temperatures and pressures in air” (DOI: 10.1063/1.4941095). n R.T. Vanderbilt Holding Co., Inc. Celebrating 100 years of trust and service to its customers around the world. 33 Winfield Street, P.O. Box 5150, Norwalk, CT 06856-5150 800-562-2476 • F: 203-855-1220 mineralsales@vanderbiltminerals.com www.vanderbiltminerals.com See us at Ceramics Expo, booth #609 Alumina ♦ Fused Quartz ♦ Sapphire ♦ Zirconia Ceramic Membranes ♦ CeO2 Polishing Powder Crucibles ♦ Tubes & Rods ♦ Plates & Discs Alumina & Sapphire Sample Pans for Thermal Analysis Ceramic Membranes ♦ Quartz Cuvettes ♦ CeO2 Polishing Powder Agate Mortar ♦ Custom Components ADVAlue TeChnOlOgy 3470 S. Dodge Blvd., Tucson, AZ 85713 Tel: 520-514-1100 ♦ Fax: 520-747-4024 sales@advaluetech.com ♦ www.advaluetech.com 24-hour Shipment of Many In-stock Standard Sizes Custom Fabrication for Special Requests See us at Ceramics Expo, booth #819 American Ceramic Society Bulletin, Vol. 95, No. 3 | www.ceramics.org 17


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