Effects of As, P and Sb on the output voltage generation of ZnO nanowires based nanogenerator: Mitigation of screening effect by using surface modified ZnO nanowires

Abstract

Here, we report high output voltage generation by employing p-type ZnO nanowires as an integral part of vertically integrated nanowire generators (VING). Study has been carried out to generate high piezoelectric voltage by introducing impurities to ZnO nanowires from group V (P, As, Sb) elements which worked as acceptor impurities for intrinsically n-type ZnO nanowires by which reverse leakage current through nanowires has been minimized. Three distinct doping concentrations (2, 4 and 6 wt %) of (P, As, and Sb) have been incorporated in ZnO nanowires at room temperature. X-ray photoelectron spectra (XPS) has indicated the presence of SbZn–2VZn, PZn + 2VZn, AsZn–2VZn complexes acceptors for Sb, P, As doping respectively. Gradual rise in piezoelectric output voltage has been observed. P/ZnO nanowires generated output voltages of 0.9 V, 1.45 V and 1.85 V respectively. For As/ZnO nanowires, output voltages are 1.25 V, 1.51 V and 1.92 V and with Sb doping recorded voltage values are 1.78 V 2.1 V and 2.5 V respectively. To Acquire optimal output voltage doped ZnO nanowires have been further oxidized (with O2) to mitigate the screening effect and maximum voltage generated by oxidized ZnO are 2.38 V, 2.86 V, and 3.45 V respectively.