Self-assembly of noble metal nanoparticles into sub-100 nm colloidosomes with collective optical and catalytic properties

Abstract

An interfacial self-assembly strategy was developed to synthesize sub-100 nm noble metal colloidosomes, showing intriguing collective optical and catalytic properties.

Architectural Design of Self‐Assembled Hollow Superstructures

“…In a typical procedure, Pickering emulsions are stabilized by colloidal particles to facilitate their use as an effective soft template. [18a,45] Earlier researchers presented an emulsion droplet approach to fabricate capsules, allowing precise control of elasticity and showing compatibility with poly(methyl methacrylate) (PMMA) colloidal particles . The resultant capsules, also called colloidosomes, were fabricated via a water‐in‐oil process prior to their self‐assembly onto the surface of the emulsion droplets through a process of depletion‐induced interaction.…”

“…In addition, the self‐supported, rigid colloidosomes self‐assembled from ultrasmall noble metal nanoparticles were formed as a result of intimate contact between the interparticle lattices. [18a] Studies have also reported using organic ditopic molecules as covalent linkers to reinforce the assembled particles. For instance, reinforcement of a microgel colloidosome shell was realized through intermicrogel cross‐linking based on the amine‐epoxy reaction at an oil/water (O/W) interface, via amino groups of the microgel surface and organic molecule–containing epoxy end groups ( Figure A) .…”

“…[9a,b,17] Construction of shell layers of hollow superstructures from colloidal building blocks can result in generation of new material properties that are unprecedented in comparison to conventional aggregate structures. [9a,18] The successful implementation of these hollow superstructures indicates their great potential for applications in a wide range of fields ( Table 1 ), such as nanomedicine, catalysis,[16c,20] energy storage,[13b,c] and photics . It is noteworthy that assembled hollow superstructures are expected to outperform conventional nanoparticle‐constructed structures owing to their superior electrochemical performance.…”

Nanocatalosomes as Plasmonic Bilayer Shells with Interlayer Catalytic Nanospaces for Solar‐Light‐Induced Reactions

“…However, in the synthetic realm, it is immensely challenging to design and synthesize bio‐inspired next‐generation catalysts, which can have the intricate morphological features of natural systems at few‐nm scale and carry out various thermodynamically challenging and industrially useful chemical reactions, most preferably by harvesting sustainable natural solar light and thereby overcoming the fossil‐fuel‐based energy‐intensive thermal conditions . Metal‐based hollow nanostructures, such as shells, capsules, boxes, rattles, yolk‐shells, colloidosomes, and others, have drawn tremendous interest due to their unique optical, chemical and cargo‐loading properties mainly emerging from high surface area, low density and confined quantum mechanical effect . So far, in these nano or microsized nanostructures, interior (hollow)/exterior surfaces or intershell gaps can only be manipulated at several tens or hundreds nm‐scale with no control over randomly emerging few/sub‐nm cavities within the shell or intershell region which are critical for exploiting structure‐dependent physicochemical and catalytic properties .…”

Density Modulation of Embedded Nanoparticles via Spatial, Temporal, and Chemical Control Elements

“…Controlled nanoparticle growth and distribution have found applications in various fields such as catalysis,optics, biological labeling and imaging, sensing, electronic and magnetic devices, and information storage . The proposed in situ reduction method is compatible with standard microfabrication techniques and, hence, provides easy access to construct devices that utilize the collective properties of nanoparticle distribution.…”