Plasmonic and Semiconductor Nanoparticles Interfere with Stereolithographic 3D Printing

Abstract

Two-photon polymerization stereolithographic three-dimensional (3D) printing is used for manufacturing a variety of structures ranging from microdevices to refractive optics. Incorporation of nanoparticles in 3D printing offers huge potential to create even more functional nanocomposite structures. However, this is difficult to achieve since the agglomeration of the nanoparticles can occur. Agglomeration not only leads to an uneven distribution of nanoparticles in the photoresin but also induces scattering of the excitation beam and altered absorption profiles due to interparticle coupling. Thus, it is crucial to ensure that the nanoparticles do not agglomerate during any stage of the process. To achieve noninteracting and well-dispersed nanoparticles on the 3D printing process, first, the stabilization of nanoparticles in the 3D printing resin is indispensable. We achieve this by functionalizing the nanoparticles with surface-bound ligands that are chemically similar to the photoresin that allows increased nanoparticle loadings without inducing agglomeration. By systematically studying the effect of different nanomaterials (Au nanoparticles, Ag nanoparticles, and CdSe/CdZnS nanoplatelets) in the resin on the 3D printing process, we observe that both, material-specific (absorption profiles) and unspecific (radical quenching at nanoparticle surfaces) pathways co-exist by which the photopolymerization procedure is altered. This can be exploited to increase the printing resolution leading to a reduction of the minimum feature size.

Strategies for Integrating Metal Nanoparticles with Two‐Photon Polymerization Process: Toward High Resolution Functional Additive Manufacturing

“…More specifically to this study, the ability to fabricate nanoscale 3D structures containing metal nanoparticles (MeNPs) can enable advances in a range of applications from plasmonics and metamaterials to biosensors. [ 9–12 ] Hence, integration of MeNPs into 3D micro/nano‐scale structures without disturbing the quality and resolution of the 2PP processes has attracted considerable attention. Previously, the direct photoreduction of a metal salt for the in situ formation of metal structures has been reported for gold nanoparticles (AuNPs), [ 13–15 ] and conductive silver nanowires and micropillars.…”

Vat photopolymerization-based 3D printing of polymer nanocomposites: current trends and applications

“…There are many factors that affect their electrical and thermal conductivity, including filler concentration and matrix type. 155…”

“…There are many factors that affect their electrical and thermal conductivity, including ller concentration and matrix type. 155 Pezzana et al printed polydimethylsiloxane (PDSM)-based polymer nanocomposites with enhanced thermal conductivity using boron nitride nanollers by DLP 3D printing. Before printing, the viscosity and reactivity of different formulations were checked.…”

Quantum Dots Facilitate 3D Two‐Photon Laser Lithography

“…For example, Peng et al [ 32 ] reported that the presence of semiconductor QDs dispersed in PETA improves the spatial resolution of structures obtained by DLW based on TPP. The effect was attributed to the additional photon absorption by the QDs during writing and thus the decreased number of photons absorbed by the photoinitiator, which, in turn, led to the reduction of the voxel size and enhanced resolution; Later, Momper et al [ 46 ] also demonstrated that the addition of CdSe/ZnCdS nanoplatelets functionalized by thiol‐terminated poly(methyl methacrylate) in a commercial acrylate‐based resin can be exploited to increase TPP‐based 3D printing resolution. In this case, other than reducing the photon absorption by the photoinitiator, the effect was further attributed to the radical quenching caused by the nanoplatelets.…”