Loading...
Enhanced carrier concentration of Fe doped delafossite CuAlO2 by double-effect: Divalent metal ions doping and excess oxygen
Author(s)
Daichakomphu, Noppanut
Harnwunggmoung, Adul
Puarporn, Yingyot
Chanlek, Narong
Date Issued
December 15, 2018
Type
Article
Abstract
Bulk CuAlO2 compound has been widely studied as a p-type metal oxide semiconductor material due to the simplicity in its synthesis and use of inexpensive raw materials. The Fe doping in CuAlO2 has been demonstrated to enhance the electrical conductivity. An in-depth analysis of the effect of Fe doping in CuAlO2 on the carrier concentration improvement was revealed. Delafossite CuAl1−xFexO2 powders with x = 0.00, 0.05, 0.10, 0.15, 0.20 and 0.30 were synthesized by a solid-state reaction method. The X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) studies were used to measure the atomic-ion concentrations and the oxidation state of each element. The variations of carrier concentration corresponded with a ratio of Cu2+/Cu1+ in CuAlO2. We found that the increase of Cu2+/Cu1+ was caused by double effects through divalent metal ions (Fe2+) doping and excess oxygen (O2−δ) in CuAlO2. The maximum carrier concentration of 8.09 × 1017 cm−3 was obtained for the CuAlO2 sample at Fe content of 10 at.%.
Citation
Solid State Ionics, 328, 17-24, 2018