A composite cermet consisting in a Ni-Fe alloy and Ce0.9Gd0.1O2-x (CGO) was prepared and used as an electrocatalytic pre-layer in a conventional solid oxide electrolyser (SOEC) for the co-electrolysis of H2O and CO2. The electrocatalyst showed two main phases ascribed to trevorite (Ni-Fe2O4, 78 wt %) and metallic Ni (22 wt %) and an average crystallite size of 27 nm. The role of the Ni-Fe electrocatalyst in promoting CH4 formation was analysed by comparing gas-chromatographic and electrochemical results obtained for coated and bare cells. A slight increase of series resistance was observed for the coated cell (0.85 vs 0.53 Omega cm(2)) at 525 degrees C. However, the coated cell demonstrated an enhanced CH4 production in the entire temperature range investigated (525-800 degrees C). Contrarily to what observed for the bare cell which mainly produced syngas, the coated cell allowed to achieve a high yield of methane (between 67% at 525 degrees C and 35% at 800 degrees C) with selectivity to CH4 between 94% at 525 degrees C and 51% at 800 degrees C. The selectivity to CO for the coated cell was relatively low (between 6% at 525 degrees C and 48% at 800 degrees C). Whereas, the bare cell showed 98-100% selectivity to CO along the entire temperature range). Durability studies showed the possible occurrence of delamination issues as consequence of carbon formation at the interface between the supporting cathode and the electrolyte as observed from the morphological analysis of SOEC cells after operation. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.