skip to main content

DOE PAGESDOE PAGES

Title: Site identity and importance in cosubstituted bixbyite In 2O 3

The bixbyite structure of In 2O 3 has two nonequivalent, 6-coordinate cation sites and, when Sn is doped into In 2O 3, the Sn prefers the “b-site” and produces a highly conductive material. When divalent/tetravalent cation pairs are cosubstituted into In 2O 3, however, the conductivity increases to a lesser extent and the site occupancy is less understood. We examine the site occupancy in the Mg xIn 2–2xSn xO 3 and Zn xIn 2–2xSn xO 3 systems with high resolution X-ray and neutron diffraction and density functional theory computations, respectively. In these sample cases and those that are previously reported in the M xIn 2–2xSn xO 3 (M = Cu, Ni, or Zn) systems, the solubility limit is greater than 25%, ensuring that the b-site cannot be the exclusively preferred site as it is in Sn:In 2O 3. Prior to this saturation point, we report that the M 2+ cation always has at least a partial occupancy on the d-site and the Sn 4+ cation has at least a partial occupancy on the b-site. The energies of formation for these configurations are highly favored, and prefer that the divalent and tetravalent substitutes are adjacent in the crystal lattice, which suggestsmore » short range ordering. Diffuse reflectance and 4-point probe measurements of Mg xIn 2–xSn xO 3 demonstrate that it can maintain an optical band gap >2.8 eV while surpassing 1000 S/cm in conductivity. Furthermore, understanding how multiple constituents occupy the two nonequivalent cation sites can provide information on how to optimize cosubstituted systems to increase Sn solubility while maintaining its dopant nature, achieving maximum conductivity.« less
Authors:
ORCiD logo [1] ;  [1] ;  [2] ;  [3] ;  [1] ;  [1]
  1. Northwestern Univ., Evanston, IL (United States)
  2. Osmaniye Korkut Ata Univ., Osmaniye (Turkey)
  3. Cukurova Univ., Adana (Turkey)
Publication Date:
Grant/Contract Number:
FG02-08ER46536
Type:
Accepted Manuscript
Journal Name:
Crystals
Additional Journal Information:
Journal Volume: 7; Journal Issue: 2; Journal ID: ISSN 2073-4352
Publisher:
MDPI
Research Org:
Northwestern Univ., Evanston, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; bixbyite; indium oxide; transparent conducting oxide
OSTI Identifier:
1356105