Effect of peptization on densification and phase transformation behaviour of sol-gel-derived nanostructured titania

Porosity reduction, packing, pore-size distribution, and anatase to rutile phase transformation behavior of nanostructured titania ceramics prepared from both peptized and unpeptized sols were studied and compared using XRD, DSC, and nitrogen-gas physisorption techniques. Precursor gels prepared from the peptized sol had a green density of about 70% after drying at 40°C, whereas the samples prepared from the unpeptized sol had a green density of only 50%. Samples prepared from the peptized sol showed higher sintering and phase transformation rates compared to the unpeptized sols.