کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
60489 47534 2016 9 صفحه PDF سفارش دهید دانلود کنید
عنوان انگلیسی مقاله ISI
Tuning chemical bonding of MnO2 through transition-metal doping for enhanced CO oxidation
ترجمه فارسی عنوان
تنظیم پیوند شیمیایی MnO2 از طریق دوپینگ فلز انتقالی برای اکسیداسیون CO افزایش یافته
کلمات کلیدی
دوپینگ؛ نانوسیم MnO2؛ اکسیداسیون CO کاتالیستی؛ محاسبه DFT
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
چکیده انگلیسی


• Fe-, Co-, Ni-, and Cu-doped α-MnO2 nanowires were synthesized by a one-step hydrothermal method.
• All doped MnO2 nanowires exhibited much enhanced CO oxidation activity.
• The Cu-doped MnO2 nanowires had a maximum TOF of 9.1 × 10−3 s−1 at 70 °C.
• Cu-doped MnO2 could maintain 50 h without obvious deactivation with 2% water moisture.
• Cu doping makes the formation of oxygen vacancies easier in MnO2.

Replacing a small fraction of cations in a host metal oxide with a different cation (also known as doping) provides a useful strategy for improving the catalytic activity. Here, we report transition metal (Fe, Co, Ni, and Cu)-doped α-MnO2 nanowires synthesized by a one-step hydrothermal method as CO oxidation catalysts. The as-prepared catalysts displayed morphology, crystal structure, and specific surface area similar to those of the pure MnO2 nanowires. A catalytic activity test showed that all doped MnO2 nanowires exhibited much enhanced CO oxidation activity, with the Cu-doped ones being the most active (TOF of 9.1 × 10−3 s−1 at 70 °C). The Cu-doped MnO2 nanowires showed nearly 100% conversion of CO at 100 °C at an hourly gas space velocity of 36,000 mL g−1 h−1, which could last for 50 h without obvious deactivation even in the presence of 2% water vapor. Density functional theory calculations suggested that Cu doping could make the formation of oxygen vacancies in MnO2, which is the rate-determining step for CO oxidation reaction, easier than for Fe-, Co-, and Ni-doped and pristine MnO2. Our work demonstrates a facile and promising strategy for improving the catalytic activity for oxide-based catalysts, which should be applicable for a variety of different chemical reactions.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Catalysis - Volume 341, September 2016, Pages 82–90
نویسندگان
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