XRD, TEM and thermal analysis of yttrium doped boehmite nanofibres

Yttrium doped boehmite nanofibres with varying yttrium content have been prepared at low temperatures using hydrothermal treatment in the presence of the surfactant polyethylene oxide (PEO). The resultant nanofibres were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetric analysis. TEM images showed the resulting nanostructures are predominantly nanofibres when Y doping is less than 5%. When the doping was at the 10 or 20% content Y(OH)3 nanorods were formed. The nanorods show similar morphology to GaO(OH) nanorods. The doped boehmite and the subsequent nanofibres were analyzed by thermogravimetric and differential thermogravimetric methods. The boehmite nanofibres produced thermally transform at higher temperatures than boehmite crystals and boehmite platelets. In general two thermal decomposition steps are observed at around 45 and 379 degrees C assigned to dehydration and dehydroxylation. The dehydration step is attributed to interstitial water trapped between the boehmite layers. The dehydroxylation steps in the boehmite samples with doping above 3% are strongly asymmetric and additional peaks are resolved in the thermal analysis patterns. This peak becomes clear in the 10 and 20% Y doped boehmite samples and is attributed to the thermal decomposition of the Y(OH)3 nanorods.