The electro-catalytically active surfaces of mixed ionic electronic conductors (MIECs) are critically important for the operation of electrochemical devices such as solid oxide electrolyser cells (SOECs) and fuel cells (SOFCs). However, the composition and morphology of surfaces of real samples are often poorly characterized, and thus our understanding of the influence of these factors on the surface exchange reactions is rudimentary. In this work, we apply low energy ion scattering (LEIS) spectrometry and atomic force microscopy (AFM) to investigate the evolution of the surface composition and morphology of two layered perovskite type materials, showing the dynamic nature of these surfaces even at room temperature. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.