{"title":"Reactivity of graphene-supported Co clusters","authors":"","doi":"10.1016/j.susc.2024.122573","DOIUrl":null,"url":null,"abstract":"<div><p>Graphene-supported Co clusters were investigated by high-resolution XPS, TPD and IRRAS using CO as a probe molecule. CO adsorption was observed at edge, on-top and bridge/hollow sites on the as-prepared clusters. Temperature-programmed XPS showed CO dissociation at <em>T</em> > 300 K. The CO desorption temperatures were determined by TPD measurements to be 260, 320 and 400 K for CO<sup>bridge/hollow</sup>, CO<sup>edge</sup> and CO<sup>top</sup>, respectively. The CO dissociation products were used to investigate the adsorption of CO on carbon and oxygen precovered Co clusters. Site blocking by these adatoms was found resulting in the absence of CO<sup>edge</sup> (XPS and TPD) and a decrease of the CO adsorption capacity (XPS, TPD and IRRAS). Additionally, no CO dissociation was found on the precovered clusters concluding a blocking of the catalytically active sites which are the edge sites of the clusters.</p></div>","PeriodicalId":22100,"journal":{"name":"Surface Science","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0039602824001249/pdfft?md5=f0efb24aabd34a82bbfdb2d83ad2742c&pid=1-s2.0-S0039602824001249-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Surface Science","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0039602824001249","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Graphene-supported Co clusters were investigated by high-resolution XPS, TPD and IRRAS using CO as a probe molecule. CO adsorption was observed at edge, on-top and bridge/hollow sites on the as-prepared clusters. Temperature-programmed XPS showed CO dissociation at T > 300 K. The CO desorption temperatures were determined by TPD measurements to be 260, 320 and 400 K for CObridge/hollow, COedge and COtop, respectively. The CO dissociation products were used to investigate the adsorption of CO on carbon and oxygen precovered Co clusters. Site blocking by these adatoms was found resulting in the absence of COedge (XPS and TPD) and a decrease of the CO adsorption capacity (XPS, TPD and IRRAS). Additionally, no CO dissociation was found on the precovered clusters concluding a blocking of the catalytically active sites which are the edge sites of the clusters.
以 CO 为探针分子，通过高分辨率 XPS、TPD 和 IRRAS 对石墨烯支持的 Co 簇进行了研究。在所制备的团簇的边缘、顶部和桥/空心位点上观察到了 CO 吸附现象。温度编程 XPS 显示 CO 在 T > 300 K 时解离。一氧化碳解离产物被用来研究一氧化碳在碳和氧预覆盖的 Co 簇上的吸附情况。结果发现，由于这些原子的位点阻塞，没有 COedge（XPS 和 TPD），CO 吸附能力下降（XPS、TPD 和 IRRAS）。此外，在预包覆簇上也没有发现一氧化碳解离现象，这说明催化活性位点（即簇的边缘位点）被阻断了。
期刊介绍：
Surface Science is devoted to elucidating the fundamental aspects of chemistry and physics occurring at a wide range of surfaces and interfaces and to disseminating this knowledge fast. The journal welcomes a broad spectrum of topics, including but not limited to:
• model systems (e.g. in Ultra High Vacuum) under well-controlled reactive conditions
• nanoscale science and engineering, including manipulation of matter at the atomic/molecular scale and assembly phenomena
• reactivity of surfaces as related to various applied areas including heterogeneous catalysis, chemistry at electrified interfaces, and semiconductors functionalization
• phenomena at interfaces relevant to energy storage and conversion, and fuels production and utilization
• surface reactivity for environmental protection and pollution remediation
• interactions at surfaces of soft matter, including polymers and biomaterials.
Both experimental and theoretical work, including modeling, is within the scope of the journal. Work published in Surface Science reaches a wide readership, from chemistry and physics to biology and materials science and engineering, providing an excellent forum for cross-fertilization of ideas and broad dissemination of scientific discoveries.
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