Au Nanoparticles Immobilized on Honeycomb-Like Polymeric Films for Surface-Enhanced Raman Scattering (SERS) Detection

Polymers

Ting-Yu Liu¹  Ho-Wen Cheng²  Yu-An Su³  Yu-Wei Cheng³  Chia-Yen Chiang³  Chien-Hsin Wu³  Ru-Jong Jeng³ 

[1] Department of Materials Engineering, Ming Chi University of Technology, New Taipei City 24301, Taiwan;Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan;Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan;

关键词: surface-enhanced Raman scattering (SERS);    breath figure;    honeycomb-like polymeric films;    gold nanoparticles;    hot-spots resonance effects;   

DOI  :  10.3390/polym9030093

来源: DOAJ

【 摘 要 】

We have successfully developed novel surface-enhanced Raman scattering (SERS) substrates with three-dimensional (3D) porous structures for effectively improving the sensitivity and reproducibility of SERS, which can rapidly detect small molecules (rhodamine 6G as an example). Periodical arrays of the honeycomb-like substrates were fabricated by self-assembling polyurethane-co-azetidine-2,4-dione (PU-PAZ) polymers. PU-PAZ comprising amphiphilic dendrons could stabilize the phase separation between the water droplets and polymer solution, and then organize into regular porous structures during the breath figure method. Subsequently, SERS substrates were fabricated by immobilizing gold nanoparticles (AuNPs) onto the honeycomb-like films with various 3D porous structures, controlled by the different PU-PAZ concentrations and relative humidities. Results show that surface enhancement factors of honeycomb-like substrates were 20 times higher than that of flat-film substrates (control group) due to enormous hot-spots resonance effects by the 3D porous structure, verified through Raman mapping at various positions of the z-axis. Furthermore, the particle size effects were evaluated by immobilized 12 and 67 nm of AuNPs on the honeycomb-like substrates, indicating larger AuNPs could induce more pronounced hot-spots effects. The generation of hot-spots resonance to enhance Raman intensity is strongly dependent on the diameter of AuNPs and the pore size of the honeycomb-like and 3D porous substrates for label-free and rapid SERS detection.

【 授权许可】

Unknown