Effect of Passivation on Piezoelectricity of ZnO Nanowire

• 作 者: Gong Chen Pan-shuo Wang
• 机 构: Department of Physics, University of Science and Technology of China, Hefei 230026, China“,”Key Labo
• 出 处: 化学物理学报（英文版）
• 发表日期: 2020年4期
• 关键词: Piezoelectricity ZnO nanowire Passivation First-principles calculation

Surface passivation is one valuable approach to tune the properties of nanomaterials.The piezoelectric properties of hexagonal[001]ZnO nanowires with four kinds of surface passivations were investigated using the first-principles calculations.It is found that in the 50％ H(O) and 50％ Cl(Zn),50％ H(O) and 50％ F(Zn) passivations,the volume and surface effects both enhance the piezoelectric coefficient.This differs from the unpassivated cases where the surface effect was the sole source of piezoelectric enhancement.In the 100％ H,100％ Cl passivations,the piezoelectric enhancement is not possible since the surface effect is screened by surface charge with weak polarization.The study reveals that the competition between the volume effect and surface effect influences the identification of the diameter-dependence phenomenon of piezoelectric coefficients for ZnO nanowires in experiments.Moreover,theresults suggest that one effective means of improving piezoelectricity of ZnO nanowires is shrinking axial lattice or increasing surface polarization through passivation.