Author(s)

Debasis Roy, Kumaresh Haldar, Biplab Kumar Paul, Alakananda Bhattacharya, Sukhen Das, Papiya Nandy

Physics Department, Jadavpur University, Kolkata, India..

The crystallized mullite composite has been synthesized via sol-gel technique in the presence of transition metal ions such as iron and copper. The electrical resistivity and activation energy of the composites have been measured and their variation with concentration of the metal ion has been investigated. The resistivity of doped mullite decreases rapidly in the shorter temperature range and sharply in the higher temperature range. The decreasing resistivity is due to the 3d orbital electrons and the concentration of metal ions present. X-ray analysis confirms the presence of metal ions in mullite, which entered in the octahedral site. The Fe²⁺ and Cu²⁺ ions will substitute Al³⁺ ion in the octahedral site of mullite structure and most probably will be responsible for reducing the resistivity as well as the activation energy. Transition metal ion doped mullite-based ceramic can be considered as promising material as a substrate in the electronic industry, because of its reasonable atom density, its low activation characteristics, low thermal expansion coefficient and high mechanical strength. The present material we have developed has an activation energy of resistivity/band gap energy, Eg, 1.11 eV at 0.04 M concentration for Cu²⁺ ion.

Nanostructures; Sol-Gel Growth; X-Ray Diffraction; Scanning Electron Microscopy (SEM); Electrical Conductivity

Roy, D. , Haldar, K. , Paul, B. , Bhattacharya, A. , Das, S. and Nandy, P. (2013) Reduced Activation Energy of Iron and Copper Ion Doped Mullite which Can Be Used as a Substrate in Electronic Industry. Journal of Surface Engineered Materials and Advanced Technology, 3, 11-17. doi: 10.4236/jsemat.2013.33A003.