Peculiarities of the dielectric response of natural zeolite composites prepared by using zeolite and silicon powders

Koc S. O., Orbukh V. I., Eyvazova G. M., Lebedeva N. N., Salamov B. G.

SUPERLATTICES AND MICROSTRUCTURES, cilt.91, ss.269-277, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 91
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.spmi.2016.01.022
  • Dergi Adı: SUPERLATTICES AND MICROSTRUCTURES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.269-277
  • Anahtar Kelimeler: Nanoporous materials, Zeolite powder, Silicon powder, Frequency, Dielectric properties, Si concentration, CONDUCTIVITY
  • 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 (3-300 GHz) of electric field and different Si concentrations (5-33%) are non-monotonic and a maximum peak is observed. This peak position is practically independent on the frequency and its maximum is observed in zeolite composites which included 9% of the Si-powder. Also the maximum peak is decreased by about an order of magnitude when frequency increases from 500 Hz to 5 kHz. Addition of the conductive Si-particles to zeolite-powder leads to two opposite effects. Firstly, the movement of electrons in the Si-particles provides increase of DR. Secondly, cations which leaving from zeolite pores can be neutralized by the particles of Si in the intercrystalline-space. Such a peculiar mechanism for recombination of Si electrons and cations from pores leads to a reduction of DR for large silicon concentrations. Due to the fact that the contribution of free carriers in the decreasing of the DR as the frequency increases, it is consistent with the suggestion that the maximum peak decreases with increasing frequency. (C) 2016 Elsevier Ltd. All rights reserved.