Preparation and electric properties of BiFeO3 film by electrophoretic deposition

• BFO powders are single phase and have the smaller particle size and narrow size distribution.
• The well-dispersed and stable suspensions containing BFO particles were obtained by adjusting the pH value to 6.5.
• Single phase BFO films whose grain size is in the range of 250–400 nm were deposited by electrophoretic deposition.

BiFeO3 (BFO) films were synthesized by electrophoretic deposition process (EPD) using suspensions containing BFO powders. The BFO powders were prepared by sol–gel method and the effects of calcining temperature and additive on phase composition, particle size and size distribution of BFO powders have been systematically investigated. It is found that the BFO powders prepared with citric acid as chelating agent and calcined at 600 °C is single phase and have smaller particle size and narrow size distribution. And the well-dispersed and stable suspensions containing BFO particles were obtained by adjusting the pH value to 6.5. Single phase BFO films were deposited by EPD. The SEM micrographs show there are some pores in the BFO films and the grain size of films is in the range of 250–400 nm. The dielectric constant of BFO films decreases with the increase of frequency and there is a peak of dielectric loss when frequency is about 10 kHz. Moreover, the electric field and frequency dependences of ferroelectric properties in BFO films have been investigated.