Engineering of plasmonic gold nanocrystals through pulsed laser irradiation

Abstract

Gold nanocrystals (NCs) have drawn tremendous interest in the scientific community due to their unique ability to interact with light. When irradiated with ultrafast pulsed lasers, the lattice temperature of gold NCs can rapidly increase, even above the melting and evaporation thresholds, which results in strong morphological, structural, and aggregation state modifications. Thereby, ultrafast pulsed laser irradiation can lead to the formation of metastable gold nanostructures with distinctive physicochemical features. In this Perspective, we discuss the implementation of femtosecond and nanosecond pulsed lasers to engineer gold NCs. We underline the importance of controlling the heating and cooling dynamics to achieve desired reshaping and restructuring of gold NCs at temperatures below and above its melting point. In addition, we demonstrate the need for advanced electron microscopy characterization techniques and single-particle studies to understand the detailed atomistic mechanisms behind the modifications following pulsed laser irradiation. Finally, we provide our views of the evolving opportunities of ultrafast laser irradiation as a unique tool for the fabrication of unprecedented nanomaterials and catalysts from metal and multimetal NCs to semiconductors.