Plasmon‐Mediated Syntheses of Metallic Nanostructures

Abstract

The ability to prepare noble metal nanostructures of a desired composition, size, and shape enables their resulting properties to be exquisitely tailored, which has led to the use of these structures in numerous applications, ranging from medicine to electronics. The prospect of using light to guide nanoparticle reactions is extremely attractive since one can, in principle, regulate particle growth based on the ability of the nanostructures to absorb a specific excitation wavelength. Therefore, using the nature of light, one can generate a homogenous population of product nanoparticles from a heterogeneous starting population. The best example of this is afforded by plasmon-mediated syntheses of metal nanoparticles, which use visible light irradiation and plasmon excitation to drive the chemical reduction of Ag(+) by citrate. Since the initial discovery that Ag triangular prisms could be prepared by the photo-induced conversion of Ag spherical nanoparticles, plasmon-mediated synthesis has become a highly controllable technique for preparing a number of different Ag particles with tight control over shape, as well as a wide variety of Au-Ag bimetallic nanostructures. We discuss the underlying physical and chemical factors that drive structural selection and conclude by outlining some of the important design considerations for controlling particle shape as learned through studies of plasmon-mediated reactions, but applicable to all methods of noble metal nanocrystal synthesis.

A review of plasma–liquid interactions for nanomaterial synthesis

“…Seed-mediated [41,308], plasmon-mediated [309], and template-based [310][311][312] growths of anisotropic NMs are popular techniques in solution-based processes. Electrochemical method also shows the possibility for synthesizing gold nanorods [102,313,314].…”

Remote Hyperthermia, Drug Delivery and Thermometry: The Multifunctional Platform Provided by Nanoparticles

“…Using this approach thiol-decorated gold nanoparticle (GNP) was surface-functionalized with paclitaxel [50]. A different strategy for the synthesis of silver, gold and bimetallic silver-gold nanosized particles, incorporating the capability to produce different shapes, is the plasmon-mediated approach [51]. The plasmonmediated synthetic route has been successfully used to produce nanoparticles with a variety of shapes and sizes, modulated by the composition of the starting chemical reaction medium (the growth solution) and illuminating light-source characteristics.…”

“…The plasmonmediated synthetic route has been successfully used to produce nanoparticles with a variety of shapes and sizes, modulated by the composition of the starting chemical reaction medium (the growth solution) and illuminating light-source characteristics. Typically, in this chemical synthesis route, the growth solution to be light-irradiated already contains nanosized metal particles (seed particles) and surface stabilizing agents [51].…”

“…Non-spherically-shaped metallic nanoparticles, such as silver [51] and gold [66], present suitable thermometric properties strongly dependent upon the size and shape [24,62,142]. Actually, nanothermometry can be realized using different nanosized materials, as for instance the heavily-doped (Nd 3+ ) rareearth-based (LaF 3 ) nanoparticle, which has been successfully tested not only for nanothermometry but also for magnetohyperthermia [143].…”

Extraction of three-dimensional silver nanostructures with supercritical fluid

“…In such a slow reaction kinetics, a prismatic shape arises from the seeds containing planar crystallographic defects (e.g., twin planes and stacking faults). 19) If the laser power is between 20 and 30 mW, three-dimensional crystals are grown as nanotrees [ Figs. 3(b) and 3(c)].…”