Maskless Preparation of Spatially‐Resolved Plasmonic Nanoparticles on Polydimethylsiloxane via In Situ Fluoride‐Assisted Synthesis. (4th May 2021)

• Record Type: Journal Article
• Authors: Mariani, Stefano; La Mattina, Antonino Amedeo; Paghi, Alessandro; Strambini, Lucanos; Barillaro, Giuseppe
• Is Part Of: Advanced functional materials. Volume 31:Number 26(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-05-04
• Subjects: fluorescence microscopy filters -- fluoride anions -- gold nanoparticles -- in situ synthesis -- nanoparticle gradients -- polydimethylsiloxane -- silver nanoparticles -- spatially resolved plasmonics; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202100774
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Here, a fluoride‐assisted route for the controlled in‐situ synthesis of metal nanoparticles (NPs) (i.e., AgNPs, AuNPs) on polydimethylsiloxane (PDMS) is reported. The size and coverage of the NPs on the PDMS surface are modulated with time and over space during the synthetic process, leveraging the improved yield (10×) and faster kinetics (100×) of NP formation in the presence of F − ions, compared to fluoride‐free approaches. This enables the maskless preparation of both linear and step gradients and patterns of NPs in 1D and 2D on the PDMS surface. As an application in flexible plasmonics/photonics, continuous and step‐wise spatial modulations of the plasmonic features of PDMS slabs with 1D and 2D AgNP gradients on the surface are demonstrated. An excellent spatially resolved tuning of key optical parameters, namely, optical density from zero to 5 and extinction ratio up to 100 dB, is achieved with AgNP gradients prepared in AgF solution for 12 minutes; the performance are comparable to those of commercial dielectric/interference filters. When used as a rejection filter in optical fluorescence microscopy, the AgNP‐PDMS slabs are able to reject the excitation laser at 405 nm and retain the green fluorescence of microbeads (100 µm) used as test cases. Abstract : Maskless preparation of 1D and 2D gradients and patterns of metal nanoparticles (NPs) on polydimethylsiloxane (PDMS) is achieved in a few minutes through real‐time modulation of size and surface coverage of NPs formed via in situ reduction in metal solutions containing fluoride ions. The presence of F − ions tremendously improves density and kinetics of NP formation process, compared to fluoride‐free methods.