Tunable atomic termination in nano-necklace BiFeO3

We investigate the growth kinetics of BiFeO3 (BFO) nano-necklace based on first principles modeling and electrospinning experiments. A two-step layered growth mechanism is proposed to control the atomic termination of each nano-necklace. X-ray diffraction (XRD) results agree well with our model predictions; (1) samples calcined at 500 and 550 degrees C consist of FeO2 (F-F) terminated nano-necklace, (2) samples calcined at 650 degrees C consist of either BiO (B-B) or BiO and FeO2 (B-F) terminated ones. The XRD diffraction peaks are located at lower 2 theta values with a magnetic moment of 3.0 emu/g for the former and at higher 2 theta values with a decrease in the magnetic moment to 0.4 emu/g for the later samples. The activation energy associated with the growth of the nano-necklaces was experimentally determined to be 0.37 eV/atom. This study provides fundamental understanding for the long-sought layer-by-layer assembly of BFO nanostructures. (C) 2014 AIP Publishing LLC.