Size Independence and Doping Dependence of Bending Modulus in ZnO Nanowires

The bending moduli of individual pure and In-doped ZnO nanowires with different dimensions were studied in situ inside a transmission electron microscopy (TEM) using a mechanical resonance method. The results revealed that the elastic bending modulus of ZnO nanowires is dependent remarkably on doping but independent of size in the experimental nanoscaled range. Taking the structural orientation into account, doping with 17.2 at % In enhances the bending modulus of ZnO nanowires; in the [(1) over bar 010] direction by the average of 120%. The doping effect on the bending modulus of ZnO nanowires was explained by first-principles calculations.