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In this study, fabrication of anode-supported solid oxide fuel cells (SOFCs) by cold sintering process (CSP) of electrolyte and anode layers was studied for the first time. A crackfree thin layer of 8YSZ electrolyte supported by a porous NiO-8YSZ anode was obtained by using the cold sintering process at 200 °C and 450 MPa uniaxial pressure for 1 h which then was post sintered at 1225 °C in conventional furnaces. Despite the much lower post-sintering temperatures as compared to the conventional ones at about 1400 °C, a continuous electrolyte/anode interface that was free of any defects such as delamination was achieved. Monolithic electrolyte prepared under identical conditions reached 95% of its theoretical density. Utilization of the cold sintering process resulted in limited grain growth in the anode which enhanced long triple-phase boundary densities. SOFCs constructed from cold-sintered 8YSZ/NiO-8YSZ bilayers exhibited opencircuit potentials of 0.90−0.85 V at 700−800 °C, confirming a fairly dense 8YSZ electrolyte. The highest power density achieved at 800 °C was 158 mW/cm 2 , which most likely would have the potential to be improved significantly upon further decreasing the anode thickness.

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Sm0.2Ce0.8O1.9‐ 30% Na2CO3 (Sm doped ceria (SDC)‐30N) nano‐composite electrolytes were densified in a single step via cold sintering process (CSP). At 200°C and 450 MPa of uniaxial pressure, samples up to 97% of their theoretical density could be obtained. The effect of processing parameters, such as temperature, uniaxial pressure, processing duration, and moisture content, on the densification of the nano‐composite electrolytes was investigated. The thermal, microstructural, and electrical properties of nano‐composites were investigated by differential scanning calorimetry, X‐ray diffractometer, scanning electron microscope, and EIS analysis. SDC crystallite sizes were found to be around 25 nm, barely coarsened after CSP by which the true nano nature of the nano‐composite could be preserved. Because, by conventional processing high density values could not be attained and high processing temperatures in excess of 600°C had to be used, promoting particle coarsening. The highest total electrical conductivity was found to be 2.2 × 10−2 S cm−1 at 600°C, with an activation energy of 0.83 eV for SDC‐30N nano‐composites. The present investigation revealed that the implementation of cold sintering technique resulted in significant enhancements in the densification of nano‐composite electrolytes, thereby rendering them suitable for efficient utilization in SOFC applications, as compared to the conventional production methods.