In this paper, we describe the observation of nanostructure formation under microwave processing of zirconium diboride powder with aluminum oxide. These nanostructures appear to be formed from arcing resulting from a microwave‐induced electric field across conductive ZrB2 particles. Microwave heating allows process times <1 min. The arcing rapidly heated the ZrB2 and nearby alumina creating nanotubes and nanorods. The morphology of these nanostructures was characterized using scanning and transmission electron microscopy (TEM), showing ∼100 nm tube wall thicknesses with widths up to a few micrometer and lengths to 40 μm. Energy‐dispersive X‐ray spectroscopy showed the composition of the nanotubes included aluminum, oxygen, zirconium, and boron. Fast Fourier transform's of the TEM images provided characterization of the lattice parameters. Morphology, composition and crystallography resemble both single‐crystal aluminum borate and boron‐mullite nanotubes. The produced nanostructures could be used to reinforce high‐temperature materials, improve the durability of metal surfaces or as needles for intracellular drug delivery.
Ultrahigh temperature zirconium diboride nanofibers were produced by microwave arc heating using micron-sized raw powder. While microwave heating the ZrB(2) powder, the development of local arcing led to rapid heating and solidification of the samples, along with the creation of nanofibers. The morphology of these high aspect ratio nanofibers was characterized using scanning electron microscopy and transmission electron microscopy. Energy dispersive x-ray spectroscopy, electron energy loss spectroscopy and selected area electron diffraction showed the composition to contain zirconium, boron, nitrogen, aluminum and oxygen as well as the crystallographic orientation. ZrB(2) nanofiber applications include aerospace and other harsh environments.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.