Low-Temperature Growth and Characterization of Cl-Doped ZnO Nanowire Arrays

ZnO nanowire arrays with low defect densities were grown electrochemically. The nanowire morphology was significantly changed when ammonium chloride was added to the source material, and an applied potential up to −1.2 V resulted in a homogeneous distribution of the nanowires, while at −1.4 V, inhomogeneous growth was observed. Photoluminescence spectra were excited by both 248 and 325 nm lasers. A lower intensity of defect emission and a blue shift of the band edge emission peak were observed as compared to undoped ZnO. The improved quality is explained in terms of the reduction of oxygen vacancies due to the presence of chlorine. These findings may have potential in fabricating ZnO nanowires with reduced defects at low cost for optical and optoelectronic applications.