Hierarchical Nanoparticle Assemblies Formed via One-Step Catalytic Stamp Pattern Transfer

Abstract

The one-step catalytic stamp pattern transfer process is described for producing arrays of hierarchical nanoparticle assemblies. The method simply combines in situ nanoparticle synthesis triggered by free residual Si−H groups on PDMS stamps and the lift-off pattern transfer technique. No additional nanoparticle synthesis procedure is required before the pattern transfer process. Exquisitely uniform and precisely spaced hierarchical nanoparticle assemblies with designed geometry can be rapidly produced using the catalytic stamp pattern transfer process. Sequential catalytic stamp pattern transfer also is described to generate multilayered, hierarchical nanoparticle assemblies with various geometries. The hierarchical nanoparticle assemblies catalytically transferred onto the surface are not just nanoparticles but nanoparticle− polydimethylsiloxane residue composites. The in situ-synthesized nanoparticles retain optical properties. The hierarchical nanoparticle assemblies with precisely controlled geometry further show potential in the application of surface-enhanced Raman scattering. The capability of one-step catalytic stamp pattern transfer allows the scalable and reproducible fabrication of welldefined hierarchical nanoparticle assemblies.

Water-Wettable Open Plasmonic Nanocavities for Ultrasensitive Molecular Detections in Multiple Phases

“…Hierarchical metal nanostructures, similar to metal nanoparticle-on-metal film, are likely to be relatively more hydrophobic compared to nonhierarchical counterparts (e.g., metal films or metal nanoparticle monolayers). 23,24 Even if the nanocavities are produced as open space, the diffusion of external molecules in an aqueous solution would be limited unless the cavities become completely wet.…”

Microfluidic Generation of Nanomaterials for Biomedical Applications

“…In a conventional batch synthesis, the three stages are poorly controlled and inevitably occurring at the same time, thus it is technically challenging to fabricate NPs with a uniform size and desired structure . In addition, stepwise preparation of complex NPs in batch reactors is laborious and has poor reproducibility, which imposes evident restrictions on their functionalities and applications . Therefore, the intrinsic limitations of conventional batch methods have long prevented the NPs from translation to the clinic.…”

“…[89,90] In addition, stepwise preparation of complex NPs in batch reactors is laborious and has poor reproducibility, which imposes evident restrictions on their functionalities and applications. [91,92] Therefore, the intrinsic limitations of conventional batch methods have long prevented the NPs from translation to the clinic.…”

Plasmonic Stamps Fabricated by Gold Dewetting on PDMS for Catalyzing Hydrosilylation on Silicon Surfaces

“…PDMS, coated with a metal nanostructured film, is an ideal substrate as the platform for a catalytic plasmonic stamp due to its flexibility and transparency to optical wavelengths. [18][19][20][21][22][23][24][25][26][27][28] In this work, the dewetting of gold on PDMS was examined as a facile and scalable way for producing plasmonically active gold nanostructures on the stamp.…”