TITLE:
Reduced Activation Energy of Iron and Copper Ion Doped Mullite which Can Be Used as a Substrate in Electronic Industry
AUTHORS:
Debasis Roy, Kumaresh Haldar, Biplab Kumar Paul, Alakananda Bhattacharya, Sukhen Das, Papiya Nandy
KEYWORDS:
Nanostructures; Sol-Gel Growth; X-Ray Diffraction; Scanning Electron Microscopy (SEM); Electrical Conductivity
JOURNAL NAME:
Journal of Surface Engineered Materials and Advanced Technology,
Vol.3 No.3A,
September
25,
2013
ABSTRACT: 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.