Atomic Structure and 3D Shape of a Multibranched Plasmonic Nanostar from a Single Spatially Resolved Electron Diffraction Map

Autor(es)

Correa, Leonardo M. ; Fairclough, Simon M. ; Scher, Kaleigh M. R. ; Atta, Supriya ; dos Santos, Diego Pereira ; Ducati, Caterina ; Fabris, Laura ; Ugarte, Daniel

• Tipo de documento: Artigo Científico
• Fonte: ACS NANO; v. 18, n. 39, p. 11-pg., 2024-09-21.

Resumo

Despite the interest in improving the sensitivity of optical sensors using plasmonic nanoparticles (NPs) (rods, wires, and stars), the full structural characterization of complex shape nanostructures is challenging. Here, we derive from a single scanning transmission electron microscope diffraction map (4D-STEM) a detailed determination of both the 3D shape and atomic arrangement of an individual 6-branched AuAg nanostar (NS) with high-aspect-ratio legs. The NS core displays an icosahedral structure, and legs are decahedral rods attached along the 5-fold axes at the core apexes. The NS legs show an anomalous anisotropic spatial distribution (all close to a plane) due to an interplay between the icosahedral symmetry and the unzipping of the surfactant layer on the core. The results significantly improve our understanding of the star growth mechanism. This low dose diffraction mapping is promising for the atomic structure study of individual multidomain, multibranched, or multiphase NPs, even when constituted of beam-sensitive materials. (AU)

• Processo FAPESP: 14/01045-0 - Estudo por técnicas avançadas de microscopia eletrônica de agregados metálicos e materiais nanocompósitos utilizados em aplicações fotovoltaicas
• Beneficiário: Daniel Mario Ugarte
• Modalidade de apoio: Bolsas no Exterior - Pesquisa
• Processo FAPESP: 22/11983-4 - Espectroscopias com intensificação de sinal: nanomateriais, teoria e simulação computacional
• Beneficiário: Mauro Carlos Costa Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/21070-5 - Espectroscopia vibracional com resolução espacial
• Beneficiário: Mauro Carlos Costa Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Temático