WS2/WO3 heterostructure for surface-enhanced Raman spectroscopy

Advancing the creation of cost-effective, stable, and uniform surface-enhanced Raman scattering (SERS) substrates that do not rely on noble metals is a crucial objective in current SERS studies. This study introduces a straightforward synthesis of heterostructures via the oxidation treatment of two-dimensional (2D) materials. Utilizing a hydrothermal reaction, we synthesized nanoflower-like WS₂ 2D materials and subsequently fabricated WS₂/WO₃ heterostructures with exceptional controllability and reproducibility following oxidation treatment. This heterostructure, characterized by its unique surface structure and appropriate band gap, substantially improves charge transfer efficiency, thereby enhancing SERS performance. The composite substrate, which relies on a chemical enhancement mechanism, demonstrates high-sensitivity quantitative detection capabilities, achieving the detection limit for R6G molecules was established at 10⁻¹⁰ M, with an enhancement factor of 0.94 × 10⁸. Additionally, a strong linear relationship between concentration and peak intensity is observed. Moreover, the substrate exhibits outstanding stability and uniformity, along with excellent quantitative analysis capabilities for molecules such as methylene blue and crystal violet. These attributes underscore its promising potential in environmental monitoring applications.