Tunable Synthesis of Poledron Bismuth Ferrite Particles via Hydrothermal Route

Bismuth ferrite(BiFeO3) powders were hydrothermally synthesized by using Bi(NO)3?5H2O and Fe(NO)3?9H2O as starting materials,and KOH used as a mineralizer.The large-scale polyhedral BiFeO3 particles were obtained by controlling KOH concentration,heating and cooling rate.It was found that the large-scale polyhedral BiFeO3 particles were synthesized favorably at the high KOH concentrations and an appropriate cooling rate was an important factor for synthesis of high crystallinity BiFeO3 particles.The quasi-cubic and truncated cubic particles of high crystallinity were obtained at the KOH concentration of 6 and 8 mol/L with the cooling rate of 0.2℃/min,respectively.The rough cubo-octahedron,truncated octahedron particles were obtained by changing the cooling rate to 0.1℃/min.The rough truncated cubic particles with pores were obtained by changing the cooling rate to 2℃/min.Morphologies evo-lution of large-scale poledron bismuth ferrite particles were observed by scanning electron microscope.The forma-tion mechanism of the regular morphologies was also discussed.