کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
193475 459770 2009 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Electrochemical impedance spectroscopy of oxidized and hydrogen-terminated nitrogen-induced conductive ultrananocrystalline diamond
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Electrochemical impedance spectroscopy of oxidized and hydrogen-terminated nitrogen-induced conductive ultrananocrystalline diamond
چکیده انگلیسی

We have studied the electrochemical impedance spectroscopy of conductive ultrananocrystalline diamond (UNCD) modified by either oxidation or hydrogenation surface treatments. The impedance was measured in the frequency range from 0.1 Hz to 40 kHz at different DC voltages and the results fitted to an equivalent electrical circuit. Despite the complexity of the conductive UNCD surface, composed of sp3-bonded grains and grain boundaries with a high content of sp2-bonded carbon atoms, a Randles circuit with a constant phase element (CPE) for the capacitive element provided a reasonable model for both terminations. However, the parameters of the CPE were very different for each termination. Taking into account the results obtained, we propose that the interfacial impedance of oxidized UNCD is dominated by the oxidized sp2-bonded carbon atoms present at the grain boundaries, and the interfacial impedance of hydrogen-terminated UNCD is governed by both the grain boundaries and the grains.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 54, Issue 6, 15 February 2009, Pages 1909–1915
نویسندگان
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