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Plasma-Modified Dendritic Cu Catalyst for CO2 Electroreduction.

ABSTRACT: 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 C2 and C3 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 x O species in these materials under the conditions of electrocatalytic conversion of CO2 (CO2RR). Our findings shed light into the strong structure/chemical state-selectivity correlation in CO2RR and open venues for the rational design of more effective catalysts through plasma pretreatments.

SUBMITTER: Scholten F

PROVIDER: S-EPMC6559126 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Plasma-Modified Dendritic Cu Catalyst for CO2 Electroreduction.

Scholten Fabian F Sinev Ilya I Bernal Miguel M Roldan Cuenya Beatriz B

ACS catalysis 20190430 6

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 C2 and C3 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 i ...[more]

PMID: 31205798

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