ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Dielectric study of nanoporous alumina fabricated by two-step anodization technique

M. A. Mir, M. A. Shah, and P. A. Ganai

Special Lab for Nano-science, Department of Physics, National Institute of Technology Srinagar, Jammu and Kashmir, India

E-mail: mirphy93@gmail.com

Received: 13 April 2020  Accepted: 13 August 2020

Abstract:

Abstract

Nanoporous anodic alumina (NAA) samples of different porosities were synthesized by electrochemical anodization technique in two different electrolytes (C₂H₂O₄ and H₃PO₄) via two-step anodization technique. The dielectric constant and dielectric loss of porous alumina was reported and decreasing trend of dielectric constant and dielectric loss of porous alumina was observed with both applied frequency as well as its porosity. This could be due to the reason that induced dipoles were unable to follow rapid fluctuations of the applied field at higher frequency. The observed dielectric constant of NAA samples prepared in C₂H₂O₄ and H₃PO₄ solutions were 7.84 and 6.27 at 20 Hz, respectively. Owing to porous nature of the material, the resulting samples showed slightly less dielectric constant and exhibited enhanced conductivity as compared to barrier type alumina. Furthermore, a correlation between theoretical results and experimental results were established.

Graphic abstract

Keywords: Anodization; Porous alumina; Dielectric study; Electric field

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01323-x

Chemical Papers 75 (2) 503–513 (2021)