Shape-Controllable Gold Nanoparticle–MoS₂ Hybrids Prepared by Tuning Edge-Active Sites and Surface Structures of MoS₂ via Temporally Shaped Femtosecond Pulses

Abstract

Edge-active site control of MoS₂ is crucial for applications such as chemical catalysis, synthesis of functional composites, and biochemical sensing. This work presents a novel nonthermal method to simultaneously tune surface chemical (edge-active sites) and physical (surface periodic micro/nano structures) properties of MoS₂ using temporally shaped femtosecond pulses, through which shape-controlled gold nanoparticles are in situ and self-assembly grown on MoS₂ surfaces to form Au-MoS₂ hybrids. The edge-active sites with unbound sulfurs of laser-treated MoS₂ drive the reduction of gold nanoparticles, while the surface periodic structures of laser-treated MoS₂ assist the shape-controllable growth of gold nanoparticles. The proposed novel method highlights the broad application potential of MoS₂; for example, these Au-MoS₂ hybrids exhibit tunable and highly sensitive SERS activity with an enhancement factor up to 1.2 × 10⁷, indicating the marked potential of MoS₂ in future chemical and biological sensing applications.