TY - JOUR
T1 - In situ diffraction study of catalytic hydrogenation of VO2
T2 - Stable phases and origins of metallicity
AU - Filinchuk, Yaroslav
AU - Tumanov, Nikolay A.
AU - Ban, Voraksmy
AU - Ji, Heng
AU - Wei, Jiang
AU - Swift, Michael W.
AU - Nevidomskyy, Andriy H.
AU - Natelson, Douglas
PY - 2014/6/4
Y1 - 2014/6/4
N2 - Controlling electronic population through chemical doping is one way to tip the balance between competing phases in materials with strong electronic correlations. Vanadium dioxide exhibits a first-order phase transition at around 338 K between a high-temperature, tetragonal, metallic state (T) and a low-temperature, monoclinic, insulating state (M1), driven by electron-electron and electron-lattice interactions. Intercalation of VO2 with atomic hydrogen has been demonstrated, with evidence that this doping suppresses the transition. However, the detailed effects of intercalated H on the crystal and electronic structure of the resulting hydride have not been previously reported. Here we present synchrotron and neutron diffraction studies of this material system, mapping out the structural phase diagram as a function of temperature and hydrogen content. In addition to the original T and M1 phases, we find two orthorhombic phases, O1 and O2, which are stabilized at higher hydrogen content. We present density functional calculations that confirm the metallicity of these states and discuss the physical basis by which hydrogen stabilizes conducting phases, in the context of the metal-insulator transition.
AB - Controlling electronic population through chemical doping is one way to tip the balance between competing phases in materials with strong electronic correlations. Vanadium dioxide exhibits a first-order phase transition at around 338 K between a high-temperature, tetragonal, metallic state (T) and a low-temperature, monoclinic, insulating state (M1), driven by electron-electron and electron-lattice interactions. Intercalation of VO2 with atomic hydrogen has been demonstrated, with evidence that this doping suppresses the transition. However, the detailed effects of intercalated H on the crystal and electronic structure of the resulting hydride have not been previously reported. Here we present synchrotron and neutron diffraction studies of this material system, mapping out the structural phase diagram as a function of temperature and hydrogen content. In addition to the original T and M1 phases, we find two orthorhombic phases, O1 and O2, which are stabilized at higher hydrogen content. We present density functional calculations that confirm the metallicity of these states and discuss the physical basis by which hydrogen stabilizes conducting phases, in the context of the metal-insulator transition.
UR - http://www.scopus.com/inward/record.url?scp=84901918896&partnerID=8YFLogxK
U2 - 10.1021/ja503360y
DO - 10.1021/ja503360y
M3 - Article
AN - SCOPUS:84901918896
SN - 0002-7863
VL - 136
SP - 8100
EP - 8109
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 22
ER -