Gold-enhanced mechanical exfoliation method attracts broad interests in recent years, which has been widely used for preparing large-area and high-quality 2D single crystals. Even many calculations predict that there is strong interaction between Au film and the exfoliated 2D crystals, direct experimental evidence is still lacking. Here, we perform Raman spectroscopy measurements for few layer MoS₂ with and without Au film underneath. The main peaks of MoS₂ on Au film show no obvious change at higher frequency, however, the breathing and shear modes at low-frequency are suppressed, especially for breathing modes. In contrast, both breathing modes and shear modes can be detected on suspended MoS₂ and the samples are transferred from Au film to SiO₂/Si. These comparison results provide direct evidence for the existence of covalent-like quasi-bonding at the interface of Au film and the exfoliated MoS₂ crystal. This MoS₂/Au interface interaction presents a special pinning-effect for low-frequency rigid vibration. Similar pinning-effect is also discovered in WS₂/Au system. Our work reports the suppression of low-frequency Raman modes of MoS₂, WS₂ on Au film, which will deliver new inspiration for studying other interactions between layered materials and solid surfaces.

近年来，金增强的机械剥离法引起了广泛的兴趣，这种方法已被广泛用于制备大面积和高质量的二维单晶。甚至许多计算都预测Au薄膜和剥离的2D晶体之间存在很强的相互作用，仍然缺乏直接的实验证据。在这里，我们对几层MoS ₂进行拉曼光谱测量，下面有和没有Au膜。Au膜上MoS _2的主峰在较高频率下无明显变化，但是低频下的呼吸和剪切模式受到抑制，特别是对于呼吸模式。相反，可以在悬浮的MoS ₂上检测呼吸模式和剪切模式，并将样品从Au膜转移到SiO₂ /硅。这些比较结果提供了直接的证据，证明在Au薄膜和脱落的MoS ₂晶体的界面上存在类似共价键的准键合。MoS ₂ / Au界面相互作用为低频刚性振动提供了特殊的钉扎效应。在WS ₂ / Au系统中也发现了类似的钉扎效应。我们的工作报告了在Au薄膜上抑制MoS ₂，WS ₂的低频拉曼模式，这将为研究层状材料与固体表面之间的其他相互作用提供新的灵感。