The as-synthesized Eu-doped BiOCl samples were analysed for their crystallinity and purity using powder PXRD. BiOCl is a typical layered material that has an anisotropy with ferroelectric polarisation along the c-direction. If the thickness of nanosheets is higher in the c-direction. As a result of this, the ferroelectric polarization is higher due to higher the coulomb-coulomb interaction. The thickness of nanosheets is lower than polarization is lower due to lower coulomb-coulomb interaction or dipoledipole interaction and depolarization is higher. The IEF directly depends on the depolarization effect if depolarization is higher then the internal electric field is also higher. This internal electric field depends on single crystalline 2D nanosheet thickness. If the thickness is higher the IEF is lower.