中国物理B ›› 2016, Vol. 25 ›› Issue (7): 77701-077701.doi: 10.1088/1674-1056/25/7/077701

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Effect of substitution group on dielectric properties of 4H-pyrano [3, 2-c] quinoline derivatives thin films

H M Zeyada, F M El-Taweel, M M El-Nahass, M M El-Shabaan   

  1. 1 Department of Physics, Faculty of Science, Damietta University, Damietta 34517, Egypt;
    2 Department of Chemistry, Faculty of Science, Damietta University, Damietta 34517, Egypt;
    3 Department of Physics, Faculty of Education, Ain Shams University, Cairo 11757, Egypt
  • 收稿日期:2016-01-20 修回日期:2016-04-04 出版日期:2016-07-05 发布日期:2016-07-05
  • 通讯作者: M M El-Shabaan E-mail:elshabaan@gmail.com

Effect of substitution group on dielectric properties of 4H-pyrano [3, 2-c] quinoline derivatives thin films

H M Zeyada1, F M El-Taweel2, M M El-Nahass3, M M El-Shabaan1   

  1. 1 Department of Physics, Faculty of Science, Damietta University, Damietta 34517, Egypt;
    2 Department of Chemistry, Faculty of Science, Damietta University, Damietta 34517, Egypt;
    3 Department of Physics, Faculty of Education, Ain Shams University, Cairo 11757, Egypt
  • Received:2016-01-20 Revised:2016-04-04 Online:2016-07-05 Published:2016-07-05
  • Contact: M M El-Shabaan E-mail:elshabaan@gmail.com

摘要: The AC electrical conductivity and dielectrical properties of 2-amino-6-ethyl-5-oxo-4-(3-phenoxyphenyl)-5,6-dihydro-4H-pyrano[3, 2-c]quinoline-3-carbonitrile (Ph-HPQ) and 2-amino-4-(2-chlorophenyl)-6-ethyl-5-oxo-5,6-dihydro-4H-pyrano [3, 2-c] quinoline-3-carbonitrile (Ch-HPQ) thin films were determined in the frequency range of 0.5 kHz-5 MHz and the temperature range of 290-443 K. The AC electrical conduction of both compounds in thin film form is governed by the correlated barrier hopping (CBH) mechanism. Some parameters such as the barrier height, the maximum barrier height, the density of charges, and the hopping distance were determined as functions of temperature and frequency. The phenoxyphenyl group has a greater influence on those parameters than the chlorophenyl group. The AC activation energies were determined at different frequencies and temperatures. The dielectric behaviors of Ph-HPQ and Ch-HPQ were investigated using the impedance spectroscopy technique. The impedance data are presented in Nyquist diagrams for different temperatures. The Ch-HPQ films have higher impedance than the Ph-HPQ films. The real dielectric constant and dielectric loss show a remarkable dependence on the frequency and temperature. The Ph-HPQ has higher dielectric constants than the Ch-HPQ.

关键词: thin films, quinoline derivatives, dielectrical properties, correlated barrier hopping

Abstract: The AC electrical conductivity and dielectrical properties of 2-amino-6-ethyl-5-oxo-4-(3-phenoxyphenyl)-5,6-dihydro-4H-pyrano[3, 2-c]quinoline-3-carbonitrile (Ph-HPQ) and 2-amino-4-(2-chlorophenyl)-6-ethyl-5-oxo-5,6-dihydro-4H-pyrano [3, 2-c] quinoline-3-carbonitrile (Ch-HPQ) thin films were determined in the frequency range of 0.5 kHz-5 MHz and the temperature range of 290-443 K. The AC electrical conduction of both compounds in thin film form is governed by the correlated barrier hopping (CBH) mechanism. Some parameters such as the barrier height, the maximum barrier height, the density of charges, and the hopping distance were determined as functions of temperature and frequency. The phenoxyphenyl group has a greater influence on those parameters than the chlorophenyl group. The AC activation energies were determined at different frequencies and temperatures. The dielectric behaviors of Ph-HPQ and Ch-HPQ were investigated using the impedance spectroscopy technique. The impedance data are presented in Nyquist diagrams for different temperatures. The Ch-HPQ films have higher impedance than the Ph-HPQ films. The real dielectric constant and dielectric loss show a remarkable dependence on the frequency and temperature. The Ph-HPQ has higher dielectric constants than the Ch-HPQ.

Key words: thin films, quinoline derivatives, dielectrical properties, correlated barrier hopping

中图分类号:  (Dielectric thin films)

  • 77.55.-g