Pre- and post-assembly modifications of colloidal plasmonic arrays: the effect of size distribution, composition and annealing

Abstract

Templated self-assembly has emerged as one of the most versatile approaches for the fabrication of plasmonic ordered arrays composed of colloidal nanoparticle clusters, representing a valid alternative to top-down lithography...

Direct Bottom-UpIn SituGrowth: A Paradigm Shift for Studies in Wet-Chemical Synthesis of Gold Nanoparticles

“…In contrast to top-down methods, bottom-up colloidal syntheses make it possible to fabricate higher quality single-crystal nanoparticles and to tune morphology rationally. Integrating colloidal particles with substrates typically begins with nanoparticle presynthesis, followed by ligand exchange/modification of the particle surface chemistry and self-assembly. ,,− Uniform films of presynthesized gold nanoparticles can be prepared following ligand exchange and self-assembly via centrifugation, controlled solvent evaporation, ,− and assembly at liquid–liquid ,− and liquid–air interfaces. ,,− These self-assembly processes can be combined with chemically ,, or physically patterned − ,,, substrates, or soft-lithography with nanoparticle inks. ,,, The application of physically patterned stamps and substrates to assist in directing the site-specific attachment of particles is especially popular and includes capillarity-assisted particle assembly or template-assisted self-assembly. − ,,, Although there are some reports patterning premade anisotropic particles, such as nanorods , and triangles, it remains challenging to orient and to arrange anisotropic particles on substrates. While soft lithography methods ( e.g.…”

Plasmonic Response of Complex Nanoparticle Assemblies

“…However, even these approaches become slow to converge or fail altogether when nanoparticles touch or overlap, which inevitably occurs in large configurations generated from assembly simulations using coarse-grained models. The ability to predict the optical response of complex assemblies, including those from simulated nanoparticle configurations, is needed to match the complexity of emerging experimental systems − ,,, and accelerate their development.…”

Plasmonic Nanostructure Lattices for High‐Performance Sensing

“…[69] The electrical driving force for NP assembly can also induce from the conductive surface through electrophoretic/dielectrophoretic processes. [69,81,82] For example, vertically oriented, Au nanorods can be arranged into arrays due to the electric dipole moment induced along the rod by the electric field (Figure 3g). [78] Further, combining the meniscus motion of the top plate and solvent evaporation of heated substrates, capillary assembly of NPs can be realized after NPs escape from the colloidal meniscus at the solution/air interface and get trapped in trenches of a low-wetting substrate (Figure 3h).…”

“…[84] Templateinduced colloidal self-assembly of NPs also shows potential for large-scale fabrication of the 2D arrays (Figure 3j). [82,[85][86][87][88][89][90] The optical qualities of assembled arrays are typically low because of the poor control of the number of NP per unit and arrangement defects (Figure 3k) but can be improved through thermal annealing posttreatments (Figure 3l). [82,85]…”