Gold Mesostructures with Tailored Surface Topography and Their Self-Assembly Arrays for Surface-Enhanced Raman Spectroscopy

• Published in: Nano letters 2010-12, Vol.10 (12), p.5006-5013
• Main Authors: Fang, Jixiang, Du, Shuya, Lebedkin, Sergei, Li, Zhiyuan, Kruk, Robert, Kappes, Manfred, Hahn, Horst
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Methods of nanofabrication; Physics; Self-assembly; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl103161q

We report a facile particle mediated aggregation protocol to synthesize “sea urchin”-like gold mesoparticles with tailored surface topography via a secondary nucleation and growth process. Surprisingly, these multitip Au mesoparticles are capable of self-assembling into monolayer or multiple layer arrays on Si substrates with a convincing reproducibility and homogeneity over large areas. Raman measurements show that these individual sea urchin-like multitipped gold mesoparticles exhibit a high enhancement of surface-enhanced Raman scattering (SERS). In addition, the sea urchin-like mesoparticle arrays display a further enhancement of SERS by 1 or 2 orders of magnitude over the individual mesoparticle due to the formation of additional hot spots between the particles. The current protocol stands out as a potentially interesting approach for the fabrication of technologically important SERS-based sensors.