We present a novel, low-cost approach to fabricate flexible piezoelectric nanogenerators (NGs) consisting of
ZnO nanowires (NWs) on carbon fibers and foldable Au-coated ZnO NWs on paper. By using such designed
structure of the NGs, the radial ZnO NWs on a cylindrical fiber can be utilized fully and the electric output of
NG is improved. The electric output behavior of the NGs can be optionally controlled by increasing the fiber
number, adjusting the strain rate and connection modes. For the single-fiber based NGs, the output voltage is
17 mV and the current density is about 0.09 μAcm-2, and the electric output is enhanced greatly compared to
that of previous similar micro-fiber based NGs. Compared with the single-fiber based NGs, the output current
of the multi-fiber based NGs made of 200 carbon fibers increased by 100 times. The output voltage of 18 mV
and current of 35 nA are generated from the multi-fiber based NGs. The electric energy generated by the NGs is
enough to power a practical device. The developed novel NGs can be used for smart textile structures,
wearable and self-powered nanodevices.