Frequency and Si concentration dependence of dielectric spectrum of natural zeolite composites prepared by using zeolite and silicon powders

Orbukh V. I., Eyvazova G. M., Lebedeva N. N., Salamov B. G., Ozer M.

OPTOELECTRONICS AND ADVANCED MATERIALS-RAPID COMMUNICATIONS, cilt.10, ss.935-940, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 10
  • Basım Tarihi: 2016
  • Dergi Adı: OPTOELECTRONICS AND ADVANCED MATERIALS-RAPID COMMUNICATIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.935-940
  • Gazi Üniversitesi Adresli: Evet

Özet

We present the real and imaginary part of the dielectric permittivity of natural zeolite composites prepared by using zeolite and silicon powders. The dielectric response (DR) dependences on the frequency of electric field and different Si concentrations (10-50%) are non-monotonic and a peak is observed. This peak position is practically independent on the frequency and the maximum is observed in zeolite composites which included 10% of Si-powder. Also the peak decreases by about an order of magnitude when frequency increases from 500 Hz to 5 kHz. Addition of conductive Si-particles to zeolite-powder leads to two opposite effects. Firstly, the movement of electrons in the Si-particles provides an increase of DR. Secondly, cations leaving zeolite pores can be neutralized by the particles of Si in the intercrystalline-space. Such a peculiar mechanism of recombination of Si electrons and cations from pores leads to a reduction of DR for large silicon concentrations. The contribution of free carriers in the decreasing of the DR as the frequency increases is consistent with the suggestion that the maximum peak decreases with increasing frequency.