Microwave gel combustion synthesis and sinterability of Nd:GGG nanopowders

Neodymium doped gadolinium gallium oxide (Nd:GGG) nanopowders synthesized by microwave gel combustion using alanine as a fuel was reported. Metal nitrates solution with alanine fuel was combusted in microwave to give precursor. The microwave precursor powder was calcined at different temperatures from 800 to 1100 °C. Phase pure Nd:GGG formation took place at 800 to 1100 °C as observed by X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectroscopy. However particle size increased with calcinations temperature from 25 nm at 800 °C to 200 nm at 1100 °C. Nd:GGG nanopowder obtained at different calcination temperatures were compacted and sintered at 1550 °C for 3 h in air. Most densified ceramic was obtained from Nd:GGG nanopowder calcined at 1100 °C. Microstructure as observed from scanning electron microscopy (SEM) showed that the most densified ceramic, obtained from nanopowder calcined at a higher calcination temperature, had a more uniform grain-size distribution, fewer pores and greater densification. XRD of sintered sample showed retention of phase purity.

SEM of sintered pellets obtained from Nd:GGG nanopowders calcined at 800 °C (a), 900 °C (b), 1000 °C (c) and 1100 °C (d)Figure optionsDownload full-size imageDownload as PowerPoint slide