Highly aligned MnO2 nanostructure was successfully synthesized by an anodic electrodeposition. Effects of deposition parameters such as anodic current density and chemical additive on the structural morphology of the MnO2 nanostructure were examined. The pore size of the MnO2 nanostructure was increased with increasing the concentration of (NH4)(2)SO4 and also with decreasing the anodic current density. The change in morphology is closely associated with the nucleation and growth rate of MnO2 that is very sensitive to the chemical additives and anodic current density. (C) 2012 Elsevier B.V. All rights reserved.