Two-dimensional (2D) materials and soft materials are both susceptible to mechanical instabilities, such as buckling, wrinkling, folding and creasing, especially when located on surfaces. Here, we report that weak van der Waals interactions cause the interface between 2D molybdenum disulphide (MoS₂) and a soft poly(methyl methacrylate) coating to demonstrate mechanical instability and delamination. The resulting non-uniform and buckled interface greatly hampers the ability of the coating to protect the MoS₂ substrate. Also, the corrosion rate of 2D MoS₂ and quench rate of intrinsic luminescence in 2D MoS2 were significantly accelerated by the soft coating. Owing to the formation of corrosive cavities at the interface, the geometry and size of the flakes became the dominating factor, and a critical size of 2D flakes for such interfacial instability was determined based on elasticity theory. Such hazardous corrosion in a 2D material caused by a soft coating raises concern for their use in electronic packaging, and for the processing of van der Waals-layered materials for future applications.

二维（2D）材料和软材料都容易受到机械不稳定性的影响，例如屈曲，起皱，折叠和折痕，特别是当放置在表面上时。在这里，我们报道弱的范德华相互作用会导致2D二硫化钼（MoS ₂）与柔软的聚甲基丙烯酸甲酯涂层之间的界面，从而证明机械不稳定性和分层。所产生的不均匀且弯曲的界面极大地阻碍了涂层保护MoS ₂基材的能力。另外，2D MoS ₂的腐蚀速率软涂层显着加快了二维MoS2中本征发光的猝灭速率和淬灭速度。由于在界面处形成腐蚀腔，薄片的几何形状和尺寸成为主要因素，并且基于弹性理论确定了用于这种界面不稳定性的二维薄片的临界尺寸。由软涂层引起的2D材料中的此类危险腐蚀引起人们对其在电子包装中的使用以及为未来应用而加工范德华层状材料的担忧。