کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1450771 988745 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Improvement in hydrogen sorption kinetics of MgH2 with Nb hydride catalyst
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Improvement in hydrogen sorption kinetics of MgH2 with Nb hydride catalyst
چکیده انگلیسی

Nanocrystalline MgH2 with fine and evenly dispersed Nb hydride was prepared by ball milling a mixture of MgH2 and 1 mol.% NbF5. This NbH-catalyzed MgH2 desorbed 6.3 wt.% H2 in 15 min and absorbed more than 90% of its initial hydrogen capacity within 5 min at 573 K. Moreover, this fast sorption kinetics was maintained after 10 cycles. Based on X-ray diffraction and transmission electron microscopy/energy-dispersive spectroscopy analyses, it is suggested that NbF5 melts during high-energy ball milling and this promotes the formation of extremely fine, film-like Nb hydride preferentially along the grain boundaries of nanocrystalline MgH2 by a liquid/solid reaction. This unique nanostructured Nb hydride is believed to suppress the grain growth of MgH2 quite effectively and thus maintain its initial catalytic effect throughout repeated hydrogenation–dehydrogenation cycles.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 55, Issue 15, September 2007, Pages 5073–5079
نویسندگان
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