Figure 2

(a,d,g,j) TEM images of Sb₂Te₃ films prepared by assisted voltages of 0 V, 20 V, 30 V, and 40 V, respectively, (b,c; e,f; h,I; k,l) HRTEM images of the selected area correspondingly marked by the squares in (a,d,g,j). (A interface between both nanoparticles is located at the dotted curve.).