Murilo Moreira, Emmanuel Cottancin, Michel Pellarin, Lucian Roiban, Karine Masenelli-Varlot, Daniel Ugarte, Varlei Rodrigues, Matthias Hillenkamp
{"title":"Intrinsic Coexistence of Miscibility and Segregation in Gold–Silver Nanoalloys","authors":"Murilo Moreira, Emmanuel Cottancin, Michel Pellarin, Lucian Roiban, Karine Masenelli-Varlot, Daniel Ugarte, Varlei Rodrigues, Matthias Hillenkamp","doi":"10.1002/smll.202411151","DOIUrl":null,"url":null,"abstract":"Bimetallic nanoparticles are used in numerous applications in catalysis, plasmonics or fuel cell technology. The addition of the second metal to the nanoparticles allows enhancing and fine-tuning their properties by choosing their composition, size, shape and environment. However, the crucial additional parameter of chemical structure within the particle is difficult to predict and access experimentally, even though segregated core–shell structures and random alloys can have drastically different physicochemical properties. This is highlighted by the vast literature on the most studied bimetallic system, gold-silver, for which the controversy on whether gold and silver are miscible on the nanoscale or segregate persists. Here, these contradictions are solved by determining quantitatively the coexistence of an alloyed core and a 1–2 nm thick shell with gradual silver enrichment as the chemical ground state structure. Chemical reactions with the environment and meta-stable structures are furthermore identified as responsible for the contradictions in the literature. This method is applicable to other multi-metallic systems, provides benchmark input for theoretical models, and forms the basis for studying chemical rearrangements under reactive conditions in catalysis.","PeriodicalId":228,"journal":{"name":"Small","volume":"64 1","pages":""},"PeriodicalIF":13.0000,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Small","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1002/smll.202411151","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Bimetallic nanoparticles are used in numerous applications in catalysis, plasmonics or fuel cell technology. The addition of the second metal to the nanoparticles allows enhancing and fine-tuning their properties by choosing their composition, size, shape and environment. However, the crucial additional parameter of chemical structure within the particle is difficult to predict and access experimentally, even though segregated core–shell structures and random alloys can have drastically different physicochemical properties. This is highlighted by the vast literature on the most studied bimetallic system, gold-silver, for which the controversy on whether gold and silver are miscible on the nanoscale or segregate persists. Here, these contradictions are solved by determining quantitatively the coexistence of an alloyed core and a 1–2 nm thick shell with gradual silver enrichment as the chemical ground state structure. Chemical reactions with the environment and meta-stable structures are furthermore identified as responsible for the contradictions in the literature. This method is applicable to other multi-metallic systems, provides benchmark input for theoretical models, and forms the basis for studying chemical rearrangements under reactive conditions in catalysis.
期刊介绍:
Small serves as an exceptional platform for both experimental and theoretical studies in fundamental and applied interdisciplinary research at the nano- and microscale. The journal offers a compelling mix of peer-reviewed Research Articles, Reviews, Perspectives, and Comments.
With a remarkable 2022 Journal Impact Factor of 13.3 (Journal Citation Reports from Clarivate Analytics, 2023), Small remains among the top multidisciplinary journals, covering a wide range of topics at the interface of materials science, chemistry, physics, engineering, medicine, and biology.
Small's readership includes biochemists, biologists, biomedical scientists, chemists, engineers, information technologists, materials scientists, physicists, and theoreticians alike.