Composite-Hydroxide-Mediated Formation of Barium Titanate Nanocubes and Their Optical Emission Response

Manjit Borah ； D. Mohanta

《Chinese Journal of Physics》 53卷1期 (2015/02) Pp. 020804-1-11

https://doi.org/10.6122/CJP.20140804C

並列摘要

We report on a nonhazardous, low cost, and mass producible composite-hydroxidemediated (CHM) route for obtaining nanoscale barium titanate (BT) cubes. The typical edge-length of the BT nanocubes was found to be ~78 nm for a sample subjected to 18 h of heat treatment. Essentially, the nanocubes are characterized by well-defined crystal facets and edges as revealed from electron microscopy studies. Facilitated by the composite hydroxide environment, the evolution of nanocubes was believed to be due to the effect of the slow assimilation and the ripening mechanism of seed nanoparticles formed during the initial stage of synthesis. The developed nanocubes are likely to be hollow, having single crystalline facets and a line dislocation density of magnitude ~10^3 μm^(-2). The optical emission characteristics obtained from photoluminescence (PL) studies have revealed a broad, overall spectra owing to the superimposition of individual contributions that led to radiative emissions of different origin. As compared to defects and self trapped excitons observable in the visible region, the near band edge emission (~380 nm) was substantially improved in the case of samples prepared with a longer duration of heat treatment.