Fabricating AC/DC nanogenerators based on single ZnO nanowires by using a nanomanipulator in a scanning electron microscope.

Single zinc oxide nanowires (ZnO NWs) are promising for nanogenerators because of their excellent semiconducting and piezoelectric properties, but characterizing the latter efficiently is challenging. As reported here, an electrical breakdown strategy was used to construct single ZnO NWs with a specific length. With the high operability of a nanomanipulator in a scanning electron microscope, ZnO-NW-based two-probe and three-probe structures were constructed for fabricating AC/DC nanogenerators, respectively. For a ZnO NW, an AC output of between −15.31 mV and 5.82 mV was achieved, while for a DC nanogenerator, an output of ∼24.3 mV was realized. Also, the three-probe structure's output method was changed to verify the distribution of piezoelectric charges when a single ZnO NW is bent by a probe, and DC outputs of different amplitudes were achieved. This study provides a low-cost, highly convenient, and operational method for studying the AC/DC output characteristics of single NWs, which is beneficial for the further development of nanogenerators. ARTICLE HIGHLIGHTS: HIGHLIGHTS • A method for reworking NWs to a specific length was achieved using an electrical breakdown strategy based on the constructed electrical loop, and its success rate is high. • With the maneuverability provided by multiple operating units of a nanomanipulator, AC output was investigated for a single ZnO NW with a two-probe structure, as well as DC output with a three-probe structure. • In the three-probe structure, different DC outputs were achieved by changing the position of the NW–probe contact point and the wiring state of the probe, while the distribution of surface piezoelectric potential along the NW's axis was studied. [ABSTRACT FROM AUTHOR]