Electrochemical reduction of CO&lt;sub&gt;2&lt;/sub&gt; on compositionally variant Au-Pt bimetallic thin films

Ma, M.; Hansen, Heine A.; Valenti, M.; Wang, Zegao; Cao, A.; Dong, Mingdong; Smith, W.A.

doi:10.1016/j.nanoen.2017.09.043

Electrochemical reduction of CO₂ on compositionally variant Au-Pt bimetallic thin films

Title

Electrochemical reduction of CO₂ on compositionally variant Au-Pt bimetallic thin films

Author

Ma, M. (TU Delft ChemE/Materials for Energy Conversion and Storage)
Hansen, Heine A. (Technical University of Denmark)
Valenti, M. (TU Delft ChemE/Materials for Energy Conversion and Storage)
Wang, Zegao (Aarhus University)
Cao, A. (TU Delft OLD ChemE/Organic Materials and Interfaces; Eindhoven University of Technology)
Dong, Mingdong (Aarhus University)
Smith, W.A. (TU Delft ChemE/Materials for Energy Conversion and Storage)

Date

2017

Abstract

The electrocatalytic reduction of CO₂ on Au-Pt bimetallic catalysts with different compositions was evaluated, offering a platform for uncovering the correlation between the catalytic activity and the surface composition of bimetallic electrocatalysts. The Au-Pt alloy films were synthesized by a magnetron sputtering co-deposition technique with tunable composition. It was found that the syngas ratio (CO:H₂) on the Au-Pt films is able to be tuned by systematically controlling the binary composition. This tunable catalytic selectivity is attributed to the variation of binding strength of COOH and CO intermediates, influenced by the surface electronic structure (d-band center energy) which is linked to the surface composition of the bimetallic films. Notably, a gradual shift of the d-band center away from the Fermi level was observed with increasing Au content, which correspondingly reduces the binding strength of the COOH and CO intermediates, leading to the distinct catalytic activity for the reduction of CO₂ on the compositionally variant Au-Pt bimetallic films. In addition, the formation of formic acid in the bimetallic systems at reduced overpotentials and higher yield indicates that synergistic effects can facilitate reaction pathways for products that are not accessible with the individual components.

Subject

Au-Pt alloy thin films
Bimetallic catalysts
CO conversion
Electrocatalysis

To reference this document use:

http://resolver.tudelft.nl/uuid:3cf628b4-a4ba-4b45-81bb-72b71850f2d1

DOI

https://doi.org/10.1016/j.nanoen.2017.09.043

ISSN

2211-2855

Source

Nano Energy, 42, 51-57

Bibliographical note

Accepted Author Manuscript