Toward high output-power nanogenerator

In this paper, the factors that determine the power output of a piezoelectric nanowire (NW) nanogenerator (NG) have been analyzed. The output current is the sum of those contributed by all of the NWs while the output voltage is determined by the voltage generated by a single NW, the capacitance of the NW array and the system, and the contact resistance. By growing uniform ZnO NWs with diameters of similar to 100 nm and lengths of similar to 5 mu m, the output current density and output voltage of the NG was improved to similar to 8.3 mu A/cm(2) and 10 mV, respectively, which are 20-30 times higher than that we previously reported. A power generation density of similar to 83 nW/cm(2) is achieved by using a single layer NW NG. (c) 2008 American Institute of Physics.