Tunable porous nanoallotropes prepared by post-assembly etching of binary nanoparticle superlattices

Abstract

Self-assembly of inorganic nanoparticles has been used to prepare hundreds of different colloidal crystals, but almost invariably with the restriction that the particles must be densely packed. Here, we show that non-close-packed nanoparticle arrays can be fabricated through the selective removal of one of two components comprising binary nanoparticle superlattices. First, a variety of binary nanoparticle superlattices were prepared at the liquid-air interface, including several arrangements that were previously unknown. Molecular dynamics simulations revealed the particular role of the liquid in templating the formation of superlattices not achievable through self-assembly in bulk solution. Second, upon stabilization, all of these binary superlattices could be transformed into distinct "nanoallotropes"-nanoporous materials having the same chemical composition but differing in their nanoscale architectures.

Plasmonic Detection of Carbohydrate‐Mediated Biological Events

“…In contrast, well-defined plasmonic substrates can also be prepared, typically through deposition on solid supports, [56,57] leading to maximized SERS signals, as well as uniform SERS enhancement factors across the entire surface, owing to their homogenous structure, so that the reproducibility of SERS analysis is greatly improved. In contrast, well-defined plasmonic substrates can also be prepared, typically through deposition on solid supports, [56,57] leading to maximized SERS signals, as well as uniform SERS enhancement factors across the entire surface, owing to their homogenous structure, so that the reproducibility of SERS analysis is greatly improved.…”

Dynamic Spirals of Nanoparticles in Light‐Responsive Polygonal Fields

“…Promoting the self‐assembly of nano‐objects into larger, functional, dynamic materials in which the size‐related properties of these nano‐objects can be preserved, enhanced, and eventually controlled has become a contemporary field of investigations . Living systems offer compelling evidence that multiscale, sophisticated, and stimuli‐responsive architectures can be built simply by letting their smallest parts self‐organize, as dictated by their intrinsic properties.…”

Direct Synthesis and Pseudomorphic Transformation of Mixed Metal Oxide Nanostructures with Non‐Close‐Packed Hollow Sphere Arrays

“…[17] Such open structures provide good access to relatively large surfaces,making them interesting for reactive applications,i ncluding sorption and catalysis.Fabrication of ncp nanoshells with hollow interiors that offer increased accessibility typically relies on the use of ncp templates [18] or tedious manipulation of colloidal crystals with nanofabrication techniques such as etching, [19] soft lithography, [20] pulsed laser irradiation, [21] nanorobot-assisted assembly, [22] and other multi-step procedures. [23,24] However,n cp hollow sphere arrays are not expected by direct templating from aclose-packed template.The results presented here are, therefore,surprising as they establish that through control of intermolecular interactions between the surface of apolymeric CCT and precursors for am ulticomponent oxide,i tis possible to directly template interconnected arrays of ncp hollow spheres.Here we demonstrate this new method to fabricate 3D ordered, ncp hollow sphere arrays using polymeric CCTs in combination with aP echini precursor, [25] and applying it to aZ nO-CeO 2 -Al 2 O 3 ternary system. Then cp nanostructure, which features ordered arrays of alternating,i nterconnected large and small hollow spheres,i sd istinct from the inverse opal structures typically generated from colloidal crystals.…”

“…Fabrication of ncp nanoshells with hollow interiors that offer increased accessibility typically relies on the use of ncp templates [18] or tedious manipulation of colloidal crystals with nanofabrication techniques such as etching, [19] soft lithography, [20] pulsed laser irradiation, [21] nanorobot-assisted assembly, [22] and other multi-step procedures. [23,24] However,n cp hollow sphere arrays are not expected by direct templating from aclose-packed template.The results presented here are, therefore,surprising as they establish that through control of intermolecular interactions between the surface of apolymeric CCT and precursors for am ulticomponent oxide,i tis possible to directly template interconnected arrays of ncp hollow spheres.…”