Electrochemical CO2 Reduction on Bimetallic Surface Alloys: Enhanced Selectivity to CO for Co/Au(110) and to H2 for Sn/Au(110). Issue 12 (18th June 2019)

• Record Type: Journal Article
• Authors: Todoroki, Naoto; Tei, Hiroki; Miyakawa, Taku; Tsurumaki, Hiroto; Wadayama, Toshimasa
• Is Part Of: ChemElectroChem. Volume 6:Issue 12(2019)
• Page Start: 3101
• Page End: 3107
• Publication Date: 2019-06-18
• Subjects: electrochemical CO2 reduction -- surface alloy -- gold single crystal -- online electrochemical mass spectrometry -- carbon monoxide; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.201900725
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: We investigated electrochemical CO2 reduction (ECR) on 0.1 monolayer‐thick‐Co and Sn‐deposited Au(110) surfaces (Co/Au(110), and Sn/Au(110)). Scanning tunneling microscopic images showed quasi‐one‐dimensional Co and Sn islands with different aspect ratios growing along the trenches of the missing‐row direction of the (1×2) reconstructed Au(110) surface. The selectivity and partial current density of the CO and H2 evolutions correlated with those of the deposited metals. CO evolution selectivity of the former Co/Au(110) increased compared with that of the Au(110), while that of the Sn/Au(110) significantly decreased. Co/Au(110) showed 1.4‐fold higher CO evolution activity than that of the clean Au(110) at −1.35 V vs. reversible hydrogen electrode. In contrast, the H2 evolution of the latter surface was significantly enhanced at a potential lower than −0.1 V. The results showed that site separations of Au and alloying elements of Co and Sn at the topmost surface determine the ECR product selectivity of alloy electrodes. Abstract : Surface engineering : Electrochemical CO2 reduction on Co/Au(110) and Sn/Au(110) surface alloys is investigated by using online electrochemical mass spectrometry. Co effectively improves the selectivity and activity for CO generation, while Sn increases the hydrogen evolution reaction activity of Au.