High-Yield Gold Nanohydrangeas on Three-Dimensional Carbon Nanotube Foams for Surface-Enhanced Raman Scattering Sensors

Abstract

Recently, carbon nanomaterial-supported plasmonic nanocrystals used as high-performance surface-enhanced Raman scattering (SERS) substrates have attracted increasing attention due to their ultra-high sensitivity of detection. However, most of the work focuses on the design of 2-D planar substrates with traditional plasmonic structures, such as nanoparticles, nanorods, nanowires, and so forth. Here, we report a novel strategy for the preparation of high-yield Au nanohydrangeas on three-dimensional porous polydopamine (PDA)/polyvinyl alcohol (PVA)/carbon nanotube (CNT) foams. The structures and growth mechanisms of these specific Au nanocrystals are systematically investigated. PDA plays the role of both a reducing agent as well as an anchoring site for Au nanohydrangeas’ growth. We also show that the ratio of surfactant KBr to the gold precursor (HAuCl4) is key to obtain these structures in a manner of high production. Moreover, the substrate of the CNT foam–Au nanohydrangea hybrid can be employed as SERS sensors and can detect the analytes down to 10–9 M.

Application of Nanohybrid Substrates with Layer-by-Layer Self-Assembling Properties to High-Sensitivity Surface-Enhanced Raman Scattering Detection

“…21−23 with other organic/inorganic nanomaterials to improve SERS signals. 24,25 Common materials can be classified accordingly to form into sphere-like materials such as SiO 2 26 and Fe 2 O 3 , 27 thread-like materials such as carbon nanotubes (CNTs) 28 and polyvinyl alcohol (PVA) nanofibers, 29 and sheet-like materials such as nanoclays 30 and graphene. 31 The use of nanohybrids increases the dispersibility of nanoparticles, as well as the electric field strength between metal particles.…”

“…In the fields of nanotechnology and materials science, organic/inorganic hybrids are regarded as some of the most important materials of the 21st century. − Many recent studies have explored the combination of metal nanoparticles with other organic/inorganic nanomaterials to improve SERS signals. , Common materials can be classified accordingly to form into sphere-like materials such as SiO 2 and Fe 2 O 3 , thread-like materials such as carbon nanotubes (CNTs) and polyvinyl alcohol (PVA) nanofibers, and sheet-like materials such as nanoclays and graphene . The use of nanohybrids increases the dispersibility of nanoparticles, as well as the electric field strength between metal particles.…”