Oxygen Vacancy-Mediated Interfacial Charge Transfer of Au/ZnO Schottky Heterojunctions for Enhanced UV Photodegradation

Figure 2

Morphological characterization of Au/ZnO thin films with different Au sputtering times (0 s, 20 s, 40 s, and 80 s), respectively. (a) As-formed pristine ellipsoidal-like ZnO (E-ZnO). (b) top-view image of Au nanoparticle- (NP-) decorated E-ZnO with sputtering time 20 s; the inset is an enlarged view. (c) SEM images of Au NP-decorated E-ZnO with sputtering time 40 s, the inset is a magnified view. (d) Surface morphology of Au NP-decorated E-ZnO with sputtering time 80 s. (e) As-prepared pristine rod-like ZnO (R-ZnO) with enlarged view (inset). (f) Morphology of Au NP-decorated R-ZnO with sputtering time 20 s and the inset is a magnified view. (g) Side-view image of Au NP-decorated R-ZnO with sputtering time 40 s and the inset is a high-resolution view. (h) High-resolution SEM image of Au NP-decorated R-ZnO with sputtering time 80 s.

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