3D Hollow MoS2 Architecture Enabled Highly Sensitive SERS Detection

Abstract

Surface-enhanced Raman spectroscopy (SERS) technology boasts merits of fingerprint recognition, a low detection limit, high sensitivity, and straightforward operation, and holds a significant position in the realm of molecular detection (even at the single-molecule level). Recently, molybdenum disulfide (MoS₂), as a special SERS substrate, has demonstrated various advantages like high molecular compatibility and an anti-fluorescence background, thus emerging as a promising non-metal substrate. Nevertheless, so far, how to improve and achieve SERS effects comparable to metal substrates remains a challenge for MoS₂ based substrates. Therefore, this work presents and acquires a 3D hollow structured MoS₂, which can be achieved through a simple hydrothermal method. Fortunately, the substrate achieves a detection limit of 10⁻⁸ M and an enhancement factor of 10⁶ for rhodamine 6G (R6G) molecules, significantly improving the performance of the non-noble-metal MoS₂ SERS. Theoretical analysis suggests that this should be attributed to the enhanced charge transfer between the substrate and probe molecules brought by the distinct monolayer self-assembly and oxygen substitution in the 3D MoS₂ architecture. The work provides a novel method to enhance the SERS performance of 2D materials, which is readily achievable and is expected to become a key cornerstone for the development of composite substrates.