Li Ma, Nikolaos Antonios Iaktnthos Nemet, Martin Bremholm, Zhaozong Sun, Anders Koldby Vestergaard, Zheshen Li, Jeppe V. Lauritsen
{"title":"Surface compositional modification of Weyl semimetal Co3Sn2S2(0001) from vacuum to electrochemical water splitting conditions","authors":"Li Ma, Nikolaos Antonios Iaktnthos Nemet, Martin Bremholm, Zhaozong Sun, Anders Koldby Vestergaard, Zheshen Li, Jeppe V. Lauritsen","doi":"10.1016/j.apsusc.2024.162046","DOIUrl":null,"url":null,"abstract":"This study investigates the surface compositional evolution of the topological Weyl semimetal Co<sub>3</sub>Sn<sub>2</sub>S<sub>2</sub>, proposed to be an active catalyst for water splitting, from ultra high vacuum (UHV) to catalytic reaction conditions, using synchrotron X-ray spectroscopy (XPS). We found that the surface cleaved in ambient air is completely oxidized, forming Co oxides and Sn oxides/hydroxides. This surface exhibits an overpotential of 503 mV to achieve a current density of 10 mA cm<sup>−2</sup> for OER. However, the UHV-cleaved surface maintains Co<sub>3</sub>Sn<sub>2</sub>S<sub>2</sub> pristine features, showing remarkably slow kinetics compared to the air-cleaved sample. Systematically tracking the oxidation process under various exposure conditions reveals that a small amount of Sn oxides forms upon exposures to O<sub>2</sub> and H<sub>2</sub>O under UHV, while a strong interaction between Sn and liquid water occurs at atmosphere conditions. In contrast, higher exposed pressure promotes Co oxidation, resulting in the formation of Co oxides in atmospheric air, which correlates with enhanced catalytic activity. Despite unfavorable evidence regarding the surface robustness, this work provides crucial insights into Co<sub>3</sub>Sn<sub>2</sub>S<sub>2</sub> surface reactivity.","PeriodicalId":247,"journal":{"name":"Applied Surface Science","volume":"10 1","pages":""},"PeriodicalIF":6.3000,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Surface Science","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1016/j.apsusc.2024.162046","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Surface compositional modification of Weyl semimetal Co3Sn2S2(0001) from vacuum to electrochemical water splitting conditions
This study investigates the surface compositional evolution of the topological Weyl semimetal Co3Sn2S2, proposed to be an active catalyst for water splitting, from ultra high vacuum (UHV) to catalytic reaction conditions, using synchrotron X-ray spectroscopy (XPS). We found that the surface cleaved in ambient air is completely oxidized, forming Co oxides and Sn oxides/hydroxides. This surface exhibits an overpotential of 503 mV to achieve a current density of 10 mA cm−2 for OER. However, the UHV-cleaved surface maintains Co3Sn2S2 pristine features, showing remarkably slow kinetics compared to the air-cleaved sample. Systematically tracking the oxidation process under various exposure conditions reveals that a small amount of Sn oxides forms upon exposures to O2 and H2O under UHV, while a strong interaction between Sn and liquid water occurs at atmosphere conditions. In contrast, higher exposed pressure promotes Co oxidation, resulting in the formation of Co oxides in atmospheric air, which correlates with enhanced catalytic activity. Despite unfavorable evidence regarding the surface robustness, this work provides crucial insights into Co3Sn2S2 surface reactivity.
期刊介绍:
Applied Surface Science covers topics contributing to a better understanding of surfaces, interfaces, nanostructures and their applications. The journal is concerned with scientific research on the atomic and molecular level of material properties determined with specific surface analytical techniques and/or computational methods, as well as the processing of such structures.