Both undoped and Ag-doped ZnO nanostructures were prepared using an electrochemical process at temperatures between 60 and 95 degrees C. The samples were characterized by scanning electron microscopy, x-ray diffraction, energy dispersive x-ray spectroscopy, and temperature dependent photoluminescence measurements (PL). The effects of parameters such as silver nitrate concentration and the applied potential on the material growth were investigated. As grown Ag-doped samples exhibit significant differences from undoped samples as indicated by their morphology and optical properties. Furthermore, after annealing in oxygen, Ag-doped samples show different trends compared to undoped samples as evidenced by a significant decrease in defect PL emissions. Possible mechanisms for the annealing effects are discussed.