含有高排序的半孔氧化物:结构,催化性质和一氧化碳的活性位点
Dong Gu1, Chun-Jiang Jia1,2, Claudia Weidenthaler1
1Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|August 25, 2015
概括
为一氧化碳 (CO) 氧化而开发出高活性氧化物 (CoO) 催化剂. 研究人员发现,以前认为不活跃的八面协调 (II) 位,由于容易氧化为 (III),表现出显著的催化活性.
科学领域:
- 材料科学
- 催化剂
- 表面化学
背景情况:
- 具有螺旋结构的氧化物 (Co3O4) 被认为是一氧化碳 (CO) 氧化的活性催化剂.
- 传统上,八面协调的Co(3+) 被认为是活性位点,而四面协调的Co(2+) 被认为是不活性位点.
研究的目的:
- 研究一种新型中等氧化物 (CoO) 材料的催化活性.
- 确定高CO氧化活动的特定物种和协调环境.
- 探索基催化剂中八面协调的CO2+的作用.
主要方法:
- 通过低温H2降解纳米造Co3O4合成高排序的中孔性CoO.
- 介质性CoO材料的表征,显示具有八面体协调的Co2+的岩盐结构.
- 测定中性CoO和其他合成的中性螺旋体 (CuCo2O4,CoCr2O4,CoFe2O4) 的氧化催化活性.
主要成果:
- 准备的中孔性COO呈现出意想不到的高氧化活性.
- 介质性COO的高活性归因于表面CO2+的氧化到CO3+.
- CoFe2O4中的八面体协调的Co2+) 种也表现出催化活性,挑战了以前的假设.
结论:
- 八面体协调的Co2+) 位点对CO氧化具有催化作用,可能是由于它们容易氧化为Co3+).
- 这一发现扩大了对基氧化催化剂活性位点的理解.
- 这项研究强调了定制的氧化物结构对于高效的碳氧化催化物的潜力.
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