Janus MoSeS nanoscrolls for ultrasensitive detection of surface-enhanced Raman scattering

Abstract

Surface-enhanced Raman scattering (SERS) has become an indispensable molecular detection technique due to its exceptional sensitivity and selectivity. However, conventional SERS methods often rely on complex metallic nanostructures, leading to background noise and performance limitations. This study addresses these challenges by investigating the potential of Janus MoSeS nanoscrolls as SERS substrates based on a chemical enhancement mechanism to achieve ultrasensitive detection. We employed a room-temperature plasma-assisted method to synthesize Janus MoSeS, followed by the formation of nanoscroll structures to enhance Raman signal intensity. Comparative SERS experiments revealed that Janus MoSeS nanoscrolls significantly outperformed defective MoSe₂, achieving enhancement factors of 8.04 × 10¹¹ for rhodamine 6G (R6G), 1.14 × 10⁷ for methylene blue (MB) and 2.12 × 10⁸ for crystal violet (CV) detection. Findings indicate that the unique dipole orientation of Janus TMDs contributes to enhanced SERS performance, while the nanoscroll architecture maximizes the effective interaction area with probe molecules. This research presents an approach for developing metal nanoparticle-free, non-plasmonic SERS substrates, thereby advancing the field of excitonic SERS technologies.