Surface-enhanced Raman scattering and photothermal effect of hollow Au nanourchins with well-defined cavities

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology Vol. 22; no. 10
• Main Authors: Kim, Joon Ki, Park, Tae-Hyeon, Jang, Du-Jeon
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2020; Springer Nature B.V
• Subjects: Anus; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dihydroxyphenylalanine; Ethanol; Inorganic Chemistry; Lasers; Levodopa; Materials Science; Morphology; Nanoparticles; Nanotechnology; Optical Devices; Optics; Photonics; Physical Chemistry; Raman spectra; Reducing agents; Research Paper; Seeds; Silica; Silicon dioxide; Silver; Sulfur; Hollow nanoparticles; Nanotips; Chemical synthesis; Silica; Plasmonic metals
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-020-05034-y

We have prepared genuinely hollow Au nanourchins (HANUs) using SiO 2 nanoparticles (NPs) as hard templates. Ag-SiO 2 NPs were fabricated via amine-assisted reduction. Then, Au nanourchins (ANUs) were synthesized by the galvanic replacement reaction of Ag-SiO 2 NPs using l -3,4-dihydroxyphenylalanine (DOPA) as a reductant and a capping agent. The silica cores of ANUs were etched using HF ( aq ) to produce HANUs. Measuring cross sections, we have found that HANUs have well-defined hollow morphologies. Compared with nanourchins made via DOPA-mediated reduction, HANUs hardly contain residual silver because very tiny silver seeds were used as the initiation sites of galvanic replacement. HANUs have revealed large surface-enhanced Raman scattering enhancement and a significant photothermal effect under a weak illumination. Graphical Abstract