Large Scale Solution Assembly of Quantum Dot–Gold Nanorod Architectures with Plasmon Enhanced Fluorescence

Abstract

Tailoring the efficiency of fluorescent emission via plasmon-exciton coupling requires structure control on a nanometer length scale using a high-yield fabrication route not achievable with current lithographic techniques. These systems can be fabricated using a bottom-up approach if problems of colloidal stability and low yield can be addressed. We report progress on this pathway with the assembly of quantum dots (emitter) on gold nanorods (plasmonic units) with precisely controlled spacing, quantum dot/nanorod ratio, and long-term colloidal stability, which enables the purification and encapsulation of the assembled architecture in a protective silica shell. Overall, such controllability with nanometer precision allows one to synthesize stable, complex architectures at large volume in a rational and controllable manner. The assembled architectures demonstrate photoluminescent enhancement (5×) useful for applications ranging from biological sensing to advanced optical communication.

Imprinted gold 2D nanoarray for highly sensitive and convenient PSA detection via plasmon excited quantum dots

“…Although there are reports describing the plasmon excited QD fluorescence enhancement, they are only limited to assembling the QDs close to the gold nanoparticles in liquid, 20,21 or spin coating the QDs on the gold nanostructures. 22,23 There is no report of a sandwich immunoassay, e.g.…”

Atomically Precise Nanocluster Assemblies Encapsulating Plasmonic Gold Nanorods

“…On the other hand, noble metal nanoparticles, especially gold nanorods (GNRs), owing to their anisotropic surface plasmonic excitations and extreme sensitivity to chemical environments have been one of the most intensely researched nanosystems. The unique plasmonic properties of gold nanoparticles have been exploited recently to achieve plasmon‐molecular resonance coupling using small organic dye molecules as well as quantum dots . Such a plasmon‐exciton coupling shows remarkably altered fluorescence (enhanced or quenched), possibly allowing the amplification of plasmonic signals in devices.…”

Physical Confinement Promoting Formation of Cu2O–Au Heterostructures with Au Nanoparticles Entrapped within Crystalline Cu2O Nanorods

“…[1][2][3] Integrating plasmonic assemblies into semiconducting materials can increase charge injection, optical path length, and enhance absorption of near IR light. [4][5][6][7][8][9][10][11] A key challenge that dictates the performance of such metal-semiconductor hybrid materials is achieving a metal-oxide interface that is free of electrically insulating organic ligands. [12][13][14][15][16] Methods to synthesize these materials generally require careful chemical design on a case-by-case basis.…”