The hBN to wBN phase transition modified by heavy ion irradiation
نویسندگان
چکیده
Boron nitride (BN) shows similarities to carbon, having a hexagonal (graphite-like) structure (hBN) and a cubic diamond type (cBN). Under ambient temperature conditions, hBN transforms irreversibly into wurtzitic BN (wBN) at pressures above 10.8 GPa [1]. We investigated the influence of ion irradiation on this displacive phase transition using in situ Raman spectroscopy and synchrotron X-ray diffractometry (XRD). To test the phase transition, powder samples (Sigma-Aldrich) as well as single crystals (fabricated in a high temperature / high pressure procedure [2]) were pressurized in a diamond anvil cell (DAC), using rhenium as gasket and a methanol-ethanol mixture as pressure transmitting medium. A ruby crystal served as pressure gauge to be read out via fluorescence spectroscopy. After each step of pressure increase, the sample was allowed to relax for 1 h before recording XRD data.
منابع مشابه
Swift Heavy Ion Irradiation of Pressurized Boron Nitride
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