Electrical conductivity and dielectric behaviour of modified sepiolite clay: Fid-Bau Portal

Electrical conductivity and dielectric behaviour of modified sepiolite clay

Esmer, Kadir

AbstractElectrical and dielectric properties of modified sepiolite mineral taken from the Anatolia region have been investigated at room temperature. Sepiolite mineral dispersed by ultrasonic methods and saturated with Fe²⁺ by ion exchange has been oriented in a 10-K Gauss magnetic field. It has been observed that sepiolite shows a paramagnetic property in the EPR spectrum. Then, the current–voltage changes have been investigated in parallel and perpendicular directions to the magnetic field. It has been observed that while the conductivity in magnetic field direction being increases, it decreases slightly in the perpendicular direction. The capacitive measurements have been done between 10 kHz and 10 MHz, and the dielectric permittivities and the loss tangent and dielectric conductivity have been calculated. The dielectric conductivity of Fe-sepiolite is found to increase having a permanent orientation polarization due to the magnetic field. In the natural sepiolite, relaxation of O→H dipole moment polarization depending on insufficient amounts of Fe²⁺ and Fe³⁺ has increased with the effect of the electric field. Thus, overall polarization at high frequencies has been observed a very rapid decrease. The changes for both samples have been observed at 100 kHz.