Spontaneous electrochemical synthesis of one-dimensional zinc oxide (1D ZnO) nanostructure from Zn anodes in an electrochemical cell is preliminarily demonstrated. By varying the discharged current up to 165 mA, a larger amount of Zn(OH)(2) composites with few quantity of nucleation sites [Zn(OH)(4)](2-) are obtained to promote an anisotropic growth of 1D ZnO nanostructure. The morphology and the size-controlled 1D ZnO structure can achieve a larger scale than others by a inducing larger quantity of Zn(OH)(2) near the nucleation site to promote the quick reaction. Such a reaction provides a strong and distinct narrow photoluminescent spectrum for the synthesized ZnO with (100) wurtzite structure with well crystallized and expanding grain. The room temperature photoluminescence and X-ray energy-dispersive spectra indicate that the composition-ratio varied ZnO with a zinc-rich condition as well as relatively low O/Zn composition ratio is preferably obtained in KOH aqueous solution at high discharged current. Our results elucidate that the significantly decreased defect-related luminescence and enhanced bandgap UV emission is controllable via the tunable discharged current and reactive time induced optimization on the quantity of (Zn(OH)(2)) and [Zn(OH)(4)](2-) precursors. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3533386] All rights reserved.