Hi I am doing Corona poling on BaTiO3 and PDMS films applying an electric field of 10 kV/cm and maintaining a temperature (of the film) of 115 C. My Poling turns out be completely ineffective in terms of XRD. Means I can see no change between unpoled and poled films. How could this be possible?? Please help me with this.
hi,
Generally speaking, ferroelectric materials shows properties similar to that of ferromagnetic materials. That is if we want to magnetise a ferrous material, it needs to be exposed to magnetic field. Depending upon the amount of ferro substance, its susceptibility (which depends upon the crystal lattice and the atoms which forms it.) and the magnitude of the applied field determines the final magnetisation that will be acquired by the ferromagnetic substance. On the same lines, ferroelectric will follow. In the case that you have presented, i guess the applied field strength may be falling short to produce the required polarisation in the crystal of BATiO3. Even though the applied electric field is of the order of 10KV/cm (roughly 1KV/mm) may be unable to provide cognisable polarisation in your sample due to some defects/impurities present in the crystal. It will work for higher arbitrarily applied field, since we do not know the state of the purity of the crystal! Also try and check whether the sample do not have miniature perforations in it. These are the probable path ways for the arcing to take place for thin samples. Due to arcing you will never get the applied E field across the sample.
Regards
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