کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1678281 1009936 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
APT analyses of deuterium-loaded Fe/V multi-layered films
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
APT analyses of deuterium-loaded Fe/V multi-layered films
چکیده انگلیسی

Interaction of hydrogen with metallic multi-layered thin films remains as a hot topic in recent days. Detailed knowledge on such chemically modulated systems is required if they are desired for application in hydrogen energy system as storage media. In this study, the deuterium concentration profile of Fe/V multi-layer was investigated by atom probe tomography (APT) at 60 and 30 K. It is firstly shown that deuterium-loaded sample can easily react with oxygen at the Pd capping layer on Fe/V and therefore, it is highly desired to avoid any oxygen exposure after D2 loading before APT analysis. The analysis temperature also has an impact on D concentration profile. The result taken at 60 K shows clear traces of surface segregation of D atoms towards analysis surface. The observed diffusion profile of D allows us to estimate an apparent diffusion coefficient D. The calculated D at 60 K is in the order of 10−17 cm2/s, deviating 6 orders of magnitude from an extrapolated value. This was interpreted with alloying, D-trapping at defects and effects of the large extension to which the extrapolation was done. A D concentration profile taken at 30 K shows no segregation anymore and a homogeneous distribution at cD=0.05(2) D/Me, which is in good accordance with that measured in the corresponding pressure–composition isotherm.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ultramicroscopy - Volume 109, Issue 5, April 2009, Pages 631–636
نویسندگان
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