Direct Printing of Micropatterned Plasmonic Au Nanoparticle/MoS₂ Heterostructure for Ultrasensitive Surface-Enhanced...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Molybdenum disulfide (MoS2) exhibits unique electronic properties, making it promising for microelectronic and photonic devices.
• The advancement of MoS2-based devices is hindered by the lack of efficient microfabrication techniques.

Purpose of the Study:

• To present a high-resolution photoreduction technology for direct printing of MoS2 micropatterns.
• To develop an ultrasensitive surface-enhanced Raman spectroscopy (SERS) sensing platform using gold nanoparticle (AuNP)/MoS2 heterostructures.

Main Methods:

• Light-controlled growth of MoSx nanoparticle micropatterns, followed by thermal annealing to form pure MoS2 nanofilms.
• Selective growth of size and gap-controlled AuNPs on MoS2 to create self-aligned AuNP/MoS2 heterostructures.
• Utilizing the engineered substrate for SERS detection of crystal violet (CV) and 4-mercaptobenzoic acid (4-MBA).

Main Results:

• Successfully fabricated MoS2 micropatterns and AuNP/MoS2 heterostructures with controlled optical properties.
• Achieved ultrasensitive SERS detection of CV and 4-MBA down to 10^-12 M using the plasmonic substrate.
• Demonstrated significant signal enhancement due to combined electromagnetic and chemical effects.

Conclusions:

• The presented photoreduction technology enables rapid, cost-effective printing of multiscale-engineered plasmonic substrates.
• This approach offers a novel technical pathway for advancing MoS2-based micro-devices and sensing platforms.
• The AuNP/MoS2 heterostructure serves as a highly efficient substrate for ultrasensitive SERS applications.