New Design of ZnO Nanorod- and Nanowire-Based NO₂ Room-Temperature Sensors Prepared by Hydrothermal Method

Figure 3

SEM images of the ZnO NW sensor at different magnification levels: (a) head-to-head electrodes; (b) NW-NW junctions between the head of the electrodes; (c, d) high-magnification SEM image of the NWs.

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