| As the wide application of flexible electronic devices in medical,aerospace,satellite and defense fields,single-layer molybdenum disulfide（SLMo S2）can completely eliminate the obstacle during the development of flexible electronic devices due to its extremely low out-of-plane stiffness and adjustable bandgap,for which it is deemed as the most important material for the revolutionary of intelligent electronics in the new century.At present,the mechanical research of SLMo S2 has achieved certain results,but the study on its wrinkling mechanics is quite limited,which greatly restricts the application of SLMo S2 in the field of flexible electronic devices.In this paper,based on the combination of theoretical analysis and molecular dynamics simulation,the wrinkling properties of SLMo S2 are systematically studied.The effects of defects,load and morphology of substrate on the wrinkling features of SLMo S2 are mainly considered.The research is mainly summarized and organized as follows.（1）The wrinkling behavior of SLMo S2 under uniaxial compression.Based on the theory of thin plate stability,it is proved that the wrinkling critical strain of SLMo S2fully meet the theoretical prediction,but the errors become obvious in the case of small size.On this basis,the vacancy defects and the anti-position defects are researched and find that the anti-position defects present much serious influence on the critical strain than the vacancy defects.The effect of various defects on the post-buckling characteristics of SLMo S2 shows obvious difference.（2）The wrinkling behavior of SLMo S2 under in-plane shear.A theoretical model of non-local stability of SLMo S2 under shear load was established,and molecular dynamics simulation predicted non-local parameters 16.8?.Under the shear load,SLMo S2 undergoes three different stages of wrinkling,including pre-buckling stage,post-wrinkling stage and fracture stage.The wrinkling features are strongly dependent on the size,temperature,and crack type,and the length of flaw sensitivity for SLMo S2with an edge is larger than the centre.（3）The wrinkling behavior of SLMo S2 on a flanar silica substrate.It is found that the substrate has a strong inhibitory effect on the instability of SLMo S2.Based on the interface wrinkling theory,SLMo S2 undergoes two type wrinkling modes in the Si O2 substrate,including in-plane and out-of-plane stratified instability.Stress strengthening occurs in the in-of-plane mode,which strongly dependent on the chiral.In the out-of-plane mode,and the critical strain increases with the interface strength.（4）The wrinkling behavior of SLMo S2 on grooved silica substrate.The instability process of monolayer molybdenum disulfide experienced two kinds of instability paths,for which the critical height H0is proportional to the width of groove W.The critical strain of wrinkling decreases with the increase of surface period and increases with effective contact area. |
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