Iron-phosphorous layers have been deposited by pulse electrochemical technique. X-ray diffraction and transmission electron microscopy investigations showed that the structures of the deposited layers changed from amorphous to nanocrystallites containing amorphous depending on the deposition parameters. The macroscopic properties of the deposited layers were affected by the deposition parameters, which influence both the chemical composition and the resulting structure in the layers. Electrochemical measurements indicated that the electrochemical activity is very sensitive to the structure of the layers. This can be explained in terms of the structural homogeneity, because grain boundaries could act as local electrochemically active sites. (c) 2006 The Electrochemical Society.