Synthesis and characterization of pyrochlore-type yttrium titanate nanoparticles by modified sol-gel method

摘要

Pyrochlore-type yttrium titanate (Y_2Ti_2O_7) nanoparticles were successfully synthesized by a simple soft-chemistry technique viz. citric acid sol-gel method (CAM). The preparation process was monitored by X-ray diffraction, thermogravimetric-differential thermal analysis and Fourier transform-infrared experiments and the microstructures and average size of as-prepared products were characterized by transmission electron microscopy and high resolution transmission electron microscopy images. It was found that compared with traditional solid state reaction (SSR), Y_2Ti_2O_7 nanopowders were synthesized at a relatively low temperature (750°C) for shortened reaction time. Detailed analysis showed that the as-prepared Y_2Ti_2O_7 with good dispersibility and narrow size distribution were quasi-spherical;;the average size was about 20-30 nm, also, the obtained products had higher BET surface area (50 m~2/g). These properties are very helpful for a photocatalyst to achieve excellent activity and may result in better behaviour in hydrogen storage.