Improving charge transfer is the key to the performance of non-noble metal semiconductor-based surface enhanced Raman scattering (SERS) substrates. In this work, the O-incorporated 1T-MoS2 nanosheets with rich sulfur defects (ID-MoS2) are obtained by simple calcination of 1T-MoS2 nanosheets in air atmosphere. Using rhodamine 6G (R6G) as typical probe molecules, ID-MoS2 nanosheets show ultrahigh Raman enhancement effects with an enhancement factor of 1.24 × 107 due to sulfur defects and O incorporation in the 1T-MoS2 lattice. First-principle density functional theory calculations suggest that the existence of sulfur defects and O incorporation significantly increase the Fermi energy level (Ef) and electronic density of states of ID-MoS2. Moreover, O incorporation can enhance the interactions between the substrate and the adsorbed molecules through electrostatic and hydrogen bonding. All these improve the charge transfer resonance and result in the remarkable SERS activity of ID-MoS2 nanosheets. This is the first study on the increasing SERS performance of semiconductor substrates by simultaneously employing defect and dopant incorporation. This study provides an approach to optimize the performance of semiconductor-based SERS substrates.

中文翻译：

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在富含缺陷的 O 结合 1T-MoS2 纳米片上显着增加拉曼增强

改善电荷转移是基于非贵金属半导体的表面增强拉曼散射 (SERS) 衬底性能的关键。在这项工作中，通过在空气气氛中简单煅烧 1T-MoS2 纳米片，获得了具有丰富硫缺陷的含氧 1T-MoS2 纳米片（ID-MoS2）。使用罗丹明 6G (R6G) 作为典型的探针分子，由于硫缺陷和 O 在 1T-MoS2 晶格中的掺入，ID-MoS2 纳米片表现出超高的拉曼增强效应，增强因子为 1.24 × 107。第一性原理密度泛函理论计算表明，硫缺陷和 O 掺入的存在显着增加了 ID-MoS2 的费米能​​级 (Ef) 和电子态密度。而且，O掺入可以通过静电和氢键增强基材与吸附分子之间的相互作用。所有这些都改善了电荷转移共振并导致 ID-MoS2 纳米片显着的 SERS 活性。这是通过同时采用缺陷和掺杂剂掺入来提高半导体衬底的 SERS 性能的第一项研究。这项研究提供了一种优化基于半导体的 SERS 基板性能的方法。