Photoelectrochemical Stability and Alteration Products of n-Type Single-Crystal ZnO Photoanodes

Figure 10

SEM micrograph of primarily metallic Zn crystal structures formed at the surface of a ZnO electrode after electrochemical reduction under PEC cell operation for 17 hrs. The darker regions indicate areas with a higher oxygen concentration. The compositional results obtained from an EDS analysis of the indicated regions a, b, and c are shown in Table 2. The hexagonal symmetry of metallic zinc is reflected in the shape of the dendrite-like plates that form in a repetitive layered structure as shown in the micrograph.