Size-controlled synthesis of BaTiO3 nanocrystals via a hydrothermal route

The size-controlled synthesis of barium titanate (BaTiO3) nanocrystals has been achieved by a hydrothermal route with Fe doping and ethylenediamine (en) addition. The as-synthesized BaTiO3 nanocrystals were characterized with XRD, SEM, TEM, and HRTEM. The results revealed that the average particle sizes of Fe-doped samples were reduced compared to that of the sample without Fe doping, suggesting that the doping ions inhibited the crystal growth. It was also found that the average particle size decreased as the Fe doping concentration increased. Furthermore, the addition of en, which served as both solvent and capping agent, could suppress the particle growth and lead to the change in particle shape from sphere to cube by a confined effect.