Nano-powders of Na0.5K0.5NbO3 made by a sol-gel method

Sodium potassium niobate (NKN) nanoparticle powders were synthesised through the thermal decomposition of a sol-gel NKN precursor. Powders and gels were characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). Hydrated carbonate phases formed as a result of reaction with evolved vapours during organic decomposition, and by reaction of NKN powders with H2O and CO2 on exposure to air. The primary particle size of the powders increased from <50 to <250 nm as decomposition temperatures were raised from 500 to 950 degrees C.