Strain-dependent electromagnetic absorption in shear-deformed MoS2 thin films

Abstract

The mechanical/electrical properties of 2D materials are governed by structural deformation, which enables greater strain tolerance than bulk solids and allows property tuning via shear forces. However, the relationship between deformation, shear forces, and absorption properties remains poorly understood. Herein, we investigated atomic-scale deformation mechanisms in MoS2 membranes under directional shear forces induced by directional slicing. Experimental observations combined with theoretical modeling revealed a deformation mechanism aligned closely with the shear force direction. Critically, shear force direction dictated lattice deformation: in-plane forces induced minor deformation and fragmentation, whereas out-of-plane forces generated larger deformation and enabled single-layer exfoliation from multilayer structures. Concurrently, shear forces significantly enhanced the material's electromagnetic wave absorption capabilities. This work elucidates deformation mechanisms in membrane materials under shear forces and provides a pathway for optimizing their performance or designing advanced devices.