کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
191257 459716 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
First principles mechanistic study of borohydride oxidation over the Pt(1 1 1) surface
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
First principles mechanistic study of borohydride oxidation over the Pt(1 1 1) surface
چکیده انگلیسی

The mechanism of borohydride oxidation and the competing hydrolysis reaction are examined over Pt(1 1 1) using density functional theory (DFT) methods. Adsorption of BH4− over Au(1 1 1) and Pt(1 1 1) is examined. Adsorption over Pt(1 1 1) is dissociative and extremely exothermic at potentials of interest, leading to a high surface coverage of H* for which gaseous hydrogen evolution is competitive with oxidation. Elementary surface reactions oxidizing B-containing intermediates are favorable over Pt(1 1 1) at −0.85 V (SHE), consistent with experimental voltammetry results in the literature. The energetics of the initial adsorption step dictate the activity limitation of gold anodes and the selectivity limitation of platinum electrodes. This adsorption energy can be rapidly calculated with DFT methods, enabling screening of pure metals, alloys, poisons, and promoters to optimize borohydride oxidation catalyst design.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 55, Issue 3, 1 January 2010, Pages 1175–1183
نویسندگان
, ,