Synthesis and characterization of Li4SiO4 nano-powders by a water-based sol–gel process

The water-based sol–gel process for the synthesis of Li4SiO4 nano-powders was reported for the first time. LiOH·H2O and aerosil SiO2 were used as the starting materials with citric acid (C6H8O7·H2O) as the chelating agent. Li4SiO4 powders with particle size as small as 100 nm were successfully synthesized at the temperature as low as 675 °C. Phase analysis, morphology, sintering behavior of the powders and ionic conductivity of the sintered bodies were investigated systematically. The experimental results showed that the powders obtained by the water-based sol–gel process (SG) possessed excellent sinterability, exhibiting a linear shrinkage of 5.2% while sintered to 900 °C, more than 3 times that of the powders obtained by solid state reaction (SSR). The bulk conductivity of the SG sintered bodies was much higher than that of the SSR samples at the same testing temperature.