在IrO2表面容易脱
Yingxue Bian1, Minkyu Kim2, Tao Li1
1Department of Chemical Engineering, University of Florida , Gainesville, Florida 32611, United States.
Journal of the American Chemical Society
|January 30, 2018
概括
有效的乙转化至关重要. 研究表明,IrO2 ((110) 可以在室温附近选择性地产生乙烯,表面化增强了选择性.
科学领域:
- 催化剂
- 表面科学
- 材料化学
背景情况:
- 为了利用碳化合物资源,有效地将乙转化至关重要,但仍然具有挑战性.
- 乙脱是石化过程中的关键反应.
研究的目的:
- 在IrO2{110) 表面研究乙脱.
- 了解影响乙烯选择性的机制和因素.
主要方法:
- 使用温度编程反应光谱 (TPRS) 来研究乙反应.
- 密度函数理论 (DFT) 的计算提供了分子层面的见解.
主要成果:
- 乙在IrO2上形成强的复合物,C-H键裂变低于200K.
- 乙烯在350K附近消化,转化率高达40%;COx是副产品.
- 乙烯脱吸是限制速度的步骤;表面化增强了乙烯的产生并抑制了氧化.
结论:
- 在室温附近,IrO2 ((110) 有效地促进乙脱.
- 通过使氧化位点失活,提高了IrO2的表面化.
- 这项研究提供了对乙烯选择性的表面特性影响的分子见解.
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