Higher hydride formation in lanthanides through mechanical milling
ORAL
Abstract
Superhydride compounds exhibit high temperature superconductivity due to the presence of high metal-to-hydrogen ratio, but only occur at very high formation pressures. Here we discuss how modifications of lanthanide precursors using mechanical ball milling prior to synthesis in a high-pressure diamond anvil cell can lead to a hydride phase with hydrogen content above that expected from the equilibrium phase diagram and improve hydrogen reactivity. Lanthanide precursors were subjected to a cryogenic ball milling technique and then exposed to a source of hydrogen in a diamond anvil cell. X-ray diffraction at HPCAT was used to explore the phase transformations of the metal hydride phase. We found an increase in hydrogen stoichiometry with mechanical ball milling relative to as received forms of lanthanide powders.
*This work was funded by the Laboratory Directed Research and Development Program at Sandia National Laboratories (SNL). SNL is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. DOE's National Nuclear Security Administration under contract DE-NA0003525. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. DOE or the United States Government. Portions of this work were performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The instrumentation and facilities used were supported by DOE/BES (DE-FG02-99ER45775, VVS), the U.S. DOE/National Nuclear Security Administration (DE-NA-0002006, CDAC; and DE-NA0001974, HPCAT), and the National Science Foundation (DMR-1809783). The Advanced Photon Source is operated by the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
–
Presenters
Peter A Sharma
Sandia National Laboratories
Authors
Peter A Sharma
Sandia National Laboratories
Sakun Duwal
Sandia National Laboratories
Portia J Allen
Sandia National Laboratories
Colorado School of Mines
Mohana Shivana
Sandia National Laboratories
Catalin D Spataru
Sandia National Laboratories
Yue Meng
Argonne National Laboratory
HPCAT, X-ray Science Division, Argonne National Laboratory
