کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1506235 993786 2008 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Reciprocal-space and real-space neutron investigation of nanostructured Mo2C and WC
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Reciprocal-space and real-space neutron investigation of nanostructured Mo2C and WC
چکیده انگلیسی

As possible substitute materials for platinum group metal heterogeneous catalysts, high surface area carbides of the early transition metals Mo and W are of great interest. Here we report nanostructured, high surface area Mo2C and WC prepared by decomposing and carburizing ammonium paramolybdate [(NH4)6Mo7O24·4H2O] and ammonium paratungstate [(NH4)10W12O41·5H2O] in flowing 50%CH4/50%H2. Surface areas as high as 52 m2/g for Mo2C and 24 m2/g for WC were obtained, with both structures crystallizing in structures appropriate for catalytic activity. We have studied these materials using a combination of neutron diffraction Rietveld refinement, X-ray photoelectron spectroscopy, surface area measurements, and scanning transmission electron microscopy. In addition, we have used pair-distribution function (PDF) analysis of the neutron total scattering data as a means of establishing the presence of graphitic carbon in the as-prepared materials.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Sciences - Volume 10, Issue 11, November 2008, Pages 1499–1510
نویسندگان
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