Synthesis of nanocrystalline conducting composite oxides based on a non-ion selective combined complexing process for functional applications

Series of nano-structured conducting functional composite oxides were synthesized through a non-ion selective EDTA–citrate–metal complexing process, which is characterized of solution-based, insensitive to environmental parameters, such as pH and humidity, and capable of synthesis of powder in large scale. Pure phase oxides with crystalline size as small as 5 nm were obtained at low calcination temperatures for most of the compositions investigated. The obtained nanocrystalline powders show very low activation energy of 13–25 kJ/mol for grain growth, and low sintering temperature for pellet densification, which is beneficial for their functional applications, such as oxygen separation membrane and electrolyte in solid oxide fuel cells (SOFCs).