Journal of the American Chemical Society p. 9047 - 9062 (2019)
Update date:2022-08-29
Topics:
Akopov, Georgiy
Mak, Wai H.
Koumoulis, Dimitrios
Yin, Hang
Owens-Baird, Bryan
Yeung, Michael T.
Muni, Mit H.
Lee, Shannon
Roh, Inwhan
Sobell, Zachary C.
Diaconescu, Paula L.
Mohammadi, Reza
Kovnir, Kirill
Kaner, Richard B.
Single-phase metal dodecaboride solid solutions, Zr0.5Y0.5B12 and Zr0.5U0.5B12, were prepared by arc melting from pure elements. The phase purity and composition were established by powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and 10B and 11B solid-state nuclear magnetic resonance (NMR) spectroscopy. The effects of carbon addition to Zr1-xYxB12 were studied and it was found that carbon causes fast cooling and as a result rapid nucleation of grains, as well as "templating" and patterning effects of the surface morphology. The hardness of the Zr0.5Y0.5B12 phase is 47.6 ± 1.7 GPa at 0.49 N load, which is ~17% higher than that of its parent compounds, ZrB12 and YB12, with hardness values of 41.6 ± 2.6 and 37.5 ± 4.3 GPa, respectively. The hardness of Zr0.5U0.5B12 is ~54% higher than that of its UB12 parent. The dodecaborides were confirmed to be metallic by band structure calculations, diffuse reflectance UV-vis, and solid-state NMR spectroscopies. The nature of the dodecaboride colors - violet for ZrB12 and blue for YB12 - can be attributed to charge-transfer. XPS indicates that the metals are in the following oxidation states: Y3+, Zr4+, and U5+/6+. The superconducting transition temperatures (Tc) of the dodecaborides were determined to be 4.5 and 6.0 K for YB12 and ZrB12, respectively, as shown by resistivity and superconducting quantum interference device (SQUID) measurements. The Tc of the Zr0.5Y0.5B12 solid solution was suppressed to 2.5 K.
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Doi:10.1080/00397911.2017.1410175
(2018)Doi:10.1039/jr9300000431
(1930)Doi:10.1134/S1070363219110070
(2019)Doi:10.1039/c5ra22115c
(2015)Doi:10.1039/c3nj00628j
(2013)Doi:10.1021/ja01565a024
(1957)