Alloy Engineering Allows On-Demand Design of Ultrasensitive Monolayer Semiconductor SERS Substrates

作者：Xiao Tang, Xingce Fan, Jun Zhou, Shuo Wang, Mingze Li, Xiangyu Hou, Kewei Jiang, Zhenhua Ni, Bei Zhao, Qi Hao, Teng Qiu · 发表于：Nano Letters · 年份：2023 · DOI：10.1021/acs.nanolett.3c01810 · 被引用次数：71 · 研究领域：Gold and Silver Nanoparticles Synthesis and Applications、Quantum Dots Synthesis And Properties、Nanocluster Synthesis and Applications

The chemical mechanism (CM) of surface-enhanced Raman scattering (SERS) has been recognized as a decent approach to mildly amplify Raman scattering. However, the insufficient charge transfer (CT) between the SERS substrate and molecules always results in unsatisfying Raman enhancement, exerting a substantial restriction for CM-based SERS. In principle, CT is dominated by the coupling between the energy levels of a semiconductor-molecule system and the laser wavelength, whereas precise tuning of the energy levels is intrinsically difficult. Herein, two-dimensional transition-metal dichalcogenide alloys, whose energy levels can be precisely and continuously tuned over a wide range by simply adjusting their compositions, are investigated. The alloys enable on-demand construction of the CT resonance channels to cater to the requirements of a specific target molecule in SERS. The SERS signals are highly reproducible, and a clear view of the SERS dependences on the energy levels is revealed for different CT resonance terms.