In order to increase magnetization, an attempt has been made to synthesize nanostructured bismuth ferrite using high energy planetary ball milling (HEPBM). In this process local heating in HEPBM and Bivolatility has eventually led to the formation of BiFe5O12 (off stoichiometric bismuth iron garnet (BIG)). Electrical characterization has been done in order to identify the nature of defects and diffusion mechanism which has been supported by high resolution transmission electron microscopy and selected area electron diffraction images. The simultaneous analysis of current density-applied voltage (J-V) and current density-frequency (J-v) curves gives insight mechanism for defect formation and how surface charge density depends on relaxation time and frequency of field applied. (C) 2015 Elsevier B.V. All rights reserved.