ORIGINAL PAPER Dy- and Tb-doped CeO 2 -Ni cermets for solid oxide fuel cell anodes: electrochemical fabrication, structural characterization, and electrocatalytic performance Massimo Catalano 1 & Antonietta Taurino 1 & Jiangtao Zhu 2 & Peter A. Crozier 3 & Simone Dal Zilio 4 & Matteo Amati 5 & Luca Gregoratti 5 & Benedetto Bozzini 6 & Claudio Mele 6 Received: 18 April 2018 /Revised: 30 July 2018 /Accepted: 2 August 2018 # Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract Dy- and Tb-doped CeO 2 -Ni cermets for highly active solid-oxide fuel-cell (SOFC) anodes were fabricated by a one-pot elec- trodeposition process. Undoped, singly-doped, and co-doped powders were synthesized in an X-ray amorphous state, heat treated in air, and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) at different crystallization stages. In particular, in situ TEM analyses were carried out during heating in an oxygen atmosphere, in order to follow the evolution of structure and morphology and to understand the role of the dopants. The key structural effect of dopants was the inhibition of grain coarsening during heat treatment. Functional tests were carried out with micro-single chamber SOFCs, fed with a CH 4 /O 2 mixture, the anodes of which were prepared with the CeO 2 -Ni powders synthesized in this study. A correlation was established between the electrocatalytic performance and the morphology of the anodic material, pinpointing that the finer and more homogeneous nanocrystalline structure of the doped powders results in better-defined and more active catalytic sites, thus improving the performance of the cell. Keywords Solid-oxide fuel-cell . CeO 2 -Ni cermet . Dy and Tb doping . Electrodeposition . In situ TEM Introduction Solid oxide fuel cells (SOFCs) are devices capable of effective conversion of chemical energy into electricity and heat, with exceptionally low environmental impact. Their advantages over conventional power generation systems include high energy-conversion efficiency, high power density, low emis- sions of CO 2 , CO, NO X , SO 2 , and fuel flexibility. Moreover, their self-sustaining high-temperature regime naturally lends itself to cogeneration, allowing efficiencies as high as 70% [1, 2]. Nevertheless, SOFC large-scale implementation is current- ly severely restricted by electrical, chemical, and thermal ma- terial stability and durability issues, impacting both the high- (800–1000 °C) and intermediate-temperature (600–800 °C) variants [2, 3]. A host of solutions has been put forward over the years to improve the cell performance, the chief ones of which include the use of alternative electrolyte and electrode materials [4–6]. The use of composite electrode materials has been demonstrated to significantly improve the performance of fuel cells; in particular, cermets, composite materials of metals and ceramics, are particularly attractive since they offer high ionic and electronic conductivity along with high reforming and electrocatalytic activity. However, the reactivi- ty between the ceramic and the metallic phases might cause the loss of SOFC performance, owing to the shrinkage of triple phase boundary area, which is the preferable anode re- action site. * Antonietta Taurino antonietta.taurino@cnr.it 1 Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, 73100 Lecce, Italy 2 Center for Solid State Science, Arizona State University, Tempe, AZ 85287, USA 3 School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287-6106, USA 4 IOM-CNR S.S. 14, km 163.5 in Area Science Park, Basovizza, 34149 Trieste, Italy 5 Elettra-Sincrotrone Trieste S.C.p.A., s.s. 14 km 163.5 in Area Science Park, Basovizza, 34012 Trieste, Italy 6 Dipartimento di Ingegneria dell’Innovazione, Università del Salento, via Monteroni, 73100 Lecce, Italy Journal of Solid State Electrochemistry https://doi.org/10.1007/s10008-018-4064-2