Exponentially decreased surface elasticity effect on elastic property and piezoelectric property of piezoelectric nanowires

Elastic and piezoelectric properties of nanowires are strongly influenced by surface elasticity effect. In this paper, a continuum theory for describing the elastic and piezoelectric properties of nanowires was proposed. The surface elasticity effect was considered as decreasing law with increasing distance from surface, as was accepted by researchers. The decrease law was considered as exponential in this paper. This theoretical model avoided the unreasonable and non-physical interface between bulk like core and surface area of nanowires. Due to the influence of variational surface elasticity, the nonlinear and exponential surface modifications were introduced. Specifically, the surface elasticity effect on piezoelectric potential was analysed with different nanowire radii and different applied forces. The surface elasticity effect on the deflection of nanowires was also discussed in this paper. The results demonstrate that surface elasticity effect is an important factor of nanowire mechanical properties, not only elastic property but also piezoelectric property, especially for radius bellow 100 nm.