LAUSR

The edge effect on the piezoelectric characteristics of two-dimensional (2D) layered materials is crucial to the design of high performance energy storage and photoelectric devices. Nevertheless, the comprehensive understanding of edge effects on the relationship between bond relaxation and piezoelectric responses of 2D materials at the atomic-level remains puzzling. Here, we explore the piezoelectric properties of monolayer MSe2 (M = Cr, Mo, W) and reveal how piezoelectric properties depend on the size and edge type based on atomic-bond-relaxation approach and continuum medium mechanics. A comprehensive analysis reveals that monolayer MSe2 exhibits anisotropic piezoelectric behaviors. Meanwhile, the piezoelectric power output is strongly dependent on the stress direction. Our study provides a way to optimize the piezoelectricity and related properties of 2D materials for practical applications.