Active site localization of methane oxidation on Pt nanocrystals.
Active site localization of methane oxidation on Pt nanocrystals.
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DOI：
10.1038/s41467-018-05464-2
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发表时间：
2018-08-24
影响因子：
16.6
通讯作者：
Kim H
中科院分区：
文献类型：
--
作者：
Kim D;Chung M;Carnis J;Kim S;Yun K;Kang J;Cha W;Cherukara MJ;Maxey E;Harder R;Sasikumar K;K R S Sankaranarayanan S;Zozulya A;Sprung M;Riu D;Kim H
金属纳米催化剂的高催化效率归因于大的表面积与体积比和丰富的配位原子，可以降低动力学势垒。虽然已经观察到作为催化过程的结果的纳米催化剂的整体形状或尺寸的变化，在低配位位点，如边缘的结构变化，仍然知之甚少。在这里，我们报告高晶格畸变的Pt纳米晶体的边缘在非均相催化甲烷氧化的基础上原位三维布拉格相干X射线衍射成像。我们直接观察到由于氧的吸附而在边缘处的收缩。这种应变在甲烷氧化过程中增加，并在反应过程完成后恢复到原始状态。结果是在良好的协议与有限元模型，将部队，由反应分子动力学模拟确定。因此，从原位应变成像获得的反应机理为改进催化剂和设计未来的纳米结构催化材料提供了重要的见解。在纳米催化剂的低配位位点，如边缘的结构变化，仍然知之甚少。在这里，作者报告了在非均相催化甲烷氧化过程中使用原位3D布拉格相干X射线衍射成像在Pt纳米晶体边缘观察到的高晶格畸变。
High catalytic efficiency in metal nanocatalysts is attributed to large surface area to volume ratios and an abundance of under-coordinated atoms that can decrease kinetic barriers. Although overall shape or size changes of nanocatalysts have been observed as a result of catalytic processes, structural changes at low-coordination sites such as edges, remain poorly understood. Here, we report high-lattice distortion at edges of Pt nanocrystals during heterogeneous catalytic methane oxidation based on in situ 3D Bragg coherent X-ray diffraction imaging. We directly observe contraction at edges owing to adsorption of oxygen. This strain increases during methane oxidation and it returns to the original state after completing the reaction process. The results are in good agreement with finite element models that incorporate forces, as determined by reactive molecular dynamics simulations. Reaction mechanisms obtained from in situ strain imaging thus provide important insights for improving catalysts and designing future nanostructured catalytic materials. The structural changes at low-coordination sites of nanocatalysts such as edges, remain poorly understood. Here, the authors report observations of high-lattice distortion at edges of Pt nanocrystals during heterogeneous catalytic methane oxidation by using in situ 3D Bragg coherent X-ray diffraction imaging.
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影响因子：
3.7
作者：
Harder, R.;Pfeifer, M. A.;Robinson, I. K.
通讯作者：
Robinson, I. K.
DOI：
10.1088/0965-0393/18/1/015012
发表时间：
2010-01-01
影响因子：
1.8
作者：
Stukowski, Alexander
通讯作者：
Stukowski, Alexander
影响因子：
41.2
作者：
Vendelbo, S. B.;Elkjaer, C. F.;Helveg, S.
通讯作者：
Helveg, S.
影响因子：
16.6
作者：
Tada, Mizuki;Murata, Shigeaki;Iwasawa, Yasuhiro
通讯作者：
Iwasawa, Yasuhiro
影响因子：
4.1
作者：
PLIMPTON, S
通讯作者：
PLIMPTON, S