Scholten Fabian, Sinev Ilya, Bernal Miguel, Roldan Cuenya Beatriz
Department of Physics, Ruhr-University Bochum, Bochum 44780, Germany.
Interface Science Department, Fritz-Haber Institute of the Max Planck Society, Berlin 14195, Germany.
ACS Catal. 2019 Jun 7;9(6):5496-5502. doi: 10.1021/acscatal.9b00483. Epub 2019 Apr 30.
Efficient and active catalysts with high selectivity for hydrocarbons and other valuable chemicals during stable operation are crucial. We have taken advantage of low-pressure oxygen plasmas to modify dendritic Cu catalysts and were able to achieve enhanced selectivity toward C and C products. Utilizing operando spectroscopic methods such as X-ray absorption fine-structure spectroscopy (XAFS) and quasi in situ X-ray photoelectron spectroscopy (XPS), we observed that the initial presence of oxides in these catalysts before the reaction plays an inferior role in determining their catalytic performance as compared to the overall catalyst morphology. This is assigned to the poor stability of the Cu O species in these materials under the conditions of electrocatalytic conversion of CO (CORR). Our findings shed light into the strong structure/chemical state-selectivity correlation in CORR and open venues for the rational design of more effective catalysts through plasma pretreatments.
在稳定运行期间，具有高效性、活性且对烃类和其他有价值化学品具有高选择性的催化剂至关重要。我们利用低压氧等离子体对树枝状铜催化剂进行改性，并能够提高对C和C产物的选择性。利用诸如X射线吸收精细结构光谱（XAFS）和准原位X射线光电子能谱（XPS）等原位光谱方法，我们观察到与整体催化剂形态相比，这些催化剂在反应前初始存在的氧化物在决定其催化性能方面所起的作用较小。这归因于在CO电催化转化（CORR）条件下，这些材料中Cu O物种的稳定性较差。我们的研究结果揭示了CORR中强烈的结构/化学状态-选择性相关性，并为通过等离子体预处理合理设计更有效的催化剂开辟了道路。
