Synthesis of Ce0.8Sm0.2O1.9 solid electrolyte by a proteic sol-gel green method

The present study reports the synthesis of Ce0.8Sm0.2O1.9 solid electrolyte by a novel proteic sol‐gel method which uses gelatin as polymerizing agent. The as‐synthesized powder material was calcined at 700 °C for 2 h, with X‐ray diffraction revealing a single cubic phase with lattice parameter a = 0.5435 nm and theoretical density of 7.144 gcm‐3. The average crystallite size is 12 nm, as determined by the Scherrer equation. Impedance spectroscopy revealed a larger resistive contribution of the grain boundaries than that from grain bulk, which, due to its lower activation energy, tends to dominate the total conductivity above 650 °C. The total conductivity is in line with literature data for ceramics of the same composition prepared by various methods, thus confirming the potential of the proteic sol‐gel method as a green, low cost alternative synthetic route to prepare ceria‐based solid electrolytes. This study describes an environmentally friendly proteic sol‐gel route to produce ceria‐based nanopowders using natural gelatin as a polymeric precursor. The powder calcined at 700 °C presents crystallite size of 12 nm and theoretical density of 7.144 gcm−3. The properties of the obtained ceramics are comparable to most literature data, thus confirming the potential of the proposed method as a green alternative to produce fuel cell materials.