Microwave assisted sol–gel synthesis of tetragonal zirconia nanoparticles

A simple and fast synthesis of zirconia nanoparticles by microware assisted citrate sol–gel method is reported. The formation of nanoparticles was characterized by performing powder X-ray diffraction (XRD) of the samples calcined at higher temperatures. The physico-chemical characterizations were done employing techniques of Raman spectroscopy and BET surface area measurements. Fourier transform infrared spectroscopy (FTIR) was performed to analyze the band structure and functional groups. High-resolution transmission electron microscopy (HRTEM) was done for analyzing the morphology of nanoparticles and estimating the crystallite sizes. The prepared material was found to have tetragonal symmetry. The average particle sizes were found ranging ∼5–10 nm. Gelation and fast combustion seems to be the reason for smaller particle sizes.

► Zirconia nanoparticles were synthesized by the simple and most convenient microware assisted citrate sol–gel method.
► The formation of tetragonal crystalline phase t-ZrO2) was confirmed by powder XRD analysis on calcined samples.
► The morphology, particle size and microstructure was analyzed using high resolution transmission electron microscopy.
► The HRTEM data also confirms the formation of single phase t-ZrO2.
► The high-resolution TEM micrograph and SAD pattern show the crystalline perfection and long-range order in the prepared zirconia nanoparticles.
► The crystallite sizes were found in the range of ∼5–10 nm.
► Raman spectra further supports and confirms the crystalline phase as well as the specific bands to show the modes of vibration in Zr–O system.
► The present work highlights to develop a cheap and fast microwave assisted synthesis of t-ZrO2 and to characterize the samples for their structural and optical properties employing various physico-chemical methods.