Fig. 3: TEM characterization of the highly ordered SnO2 nanobowl branched ZnO NW sample S@Z20-Z5.

a Low-magnification image of two nanowire-branched nanobowls; b the highly magnified image of a randomly selected single ZnO NW on S@Z20-Z5; c the HRTEM image and d the SAED pattern obtained on a single ZnO NW