Phase transition induced improvement in H 2 desorption kinetics : the case of the high - temperature form of Y ( BH
نویسندگان
چکیده
Dry (mechanochemical) synthesis of Y(BH4)3. For mechanochemical synthesis the vibrating mill (Testchem) and chromium steel bowl and disc were used. Substrates, YCl3 and LiBH4 were mixed in ca 1:3 molar ratio (with a 5 % excess of MBH4) and milled for ca. 60 minutes in Ar atmosphere. Milling periods of 3–5 minutes were altered with 2–5 minutes rests to avoid thermal decomposition of the products. Temperature of the milling bowl did not exceed 40 °C as measured by a pyrometer.
منابع مشابه
Phase transition induced improvement in H2 desorption kinetics: the case of the high-temperature form of Y(BH4)3.
The high-temperature (HT) phase of Y(BH(4))(3) has been prepared by heating of the as mechanochemically synthesised low-temperature (LT) phase of Y(BH(4))(3) to 194-216 °C and subsequent rapid cooling to ambient temperature. Although the differences in the crystal structure and vibrational spectra for these closely-related polymorphs are rather small, yet the NMR MAS (1)H and CP MAS (89)Y spect...
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