Top-down processing of NaNbO 3 nanopowder

Abstract

We report the processing of NaNbO 3 nanopowder by combining the solid-state synthesis and subsequent milling in the agitator bead mill. The effect of different rotation speeds of the agitator shaft on the comminution process was followed by laser granulometry. The morphology and specific surface area of the powders were investigated by scanning electron microscopy and the N 2 adsorption method, respectively. With the optimized milling parameters, we obtained NaNbO 3 nanoparticles with an average size of 25nm and a narrow particle size distribution. The result is comparable to other processing techniques, such as solution-based chemical routes or mechanochemical synthesis; however, the presented method does not require any complicated processing and it can be easily upscaled to yield large quantities of the NaNbO 3 nanopowder. Furthermore, the compaction behaviour of the obtained nanopowder was investigated, and a compaction-response diagram was constructed revealing good compactability of the powder. The green compacts, isostatically pressed at 740MPa, had a relative density of 70 and a narrow pore size distribution with an average pore radius of 4nm. © 2012 Jurij Koruza et al.