Nanoscale control of molecular self-assembly induced by plasmonic hot-electron dynamics

TL;DR

This paper demonstrates nanoscale control of molecular self-assembly by using plasmonic hot-electron dynamics to precisely cleave bonds on nanoparticle surfaces with light, enabling advanced nanostructure fabrication.

Contribution

It introduces a novel method for spatially controlling molecular self-assembly using plasmonic light-induced bond cleavage at the nanoscale.

Findings

Achieved nanoscale precision in surface chemistry modification.

Enabled multiplexing and selective positioning of nanomaterials.

Demonstrated high-throughput, wavelength, and polarization-dependent control.

Abstract

Self-assembly processes allow us to design and create complex nanostructures using molecules as building blocks and surfaces as scaffolds. This autonomous driven construction is possible due to a complex thermodynamic balance of molecule-surface interactions. As such, nanoscale guidance and control over this process is hard to achieve. Here we use the highly localized light-to-chemical-energy conversion of plasmonic materials to spatially cleave Au-S bonds on pre-determined locations within a single nanoparticle, enabling unprecedented control over this archetypal system for molecular self-assembly. Our method offers nanoscale precision and high-throughput light-induced tailoring of the surface chemistry of individual and packed nano-sized metallic structures by simply varying wavelength and polarization of the incident light. Assisted by single-molecule super-resolution fluorescence microscopy, we image, quantify and shed light onto the plasmon-induced desorption mechanism. We show that plasmon-induced photo-desorption enables sub-diffraction multiplexing, selective positioning of nanomaterials and even sorting and purification of colloidal nanoparticles.