Site Dependency of the High Conductivity of Ga₂In₆Sn₂O₁₆: The Role of the 7-Coordinate Site

Abstract

The 6-coordinated cation site is the fundamental building block of the most effective transparent conducting oxides. Ga 2 In 6 Sn 2 O 16 , however, maintains 4-, 6-, 7-, and 8-coordinated cation sites and still exhibits desirable transparency and high conductivity. To investigate the potential impact of these alternative sites, we partially replace the Sn in Ga 2 In 6 Sn 2 O 16 with Ti, Zr, or Hf and use a combined approach of density functional theory-based calculations, X-ray diffraction, and neutron diffraction to establish that the substitution occurs preferentially on the 7-coordinate site. In contrast to Sn, the empty d orbitals of Ti, Zr, and Hf promote spd covalency with the surrounding oxygen, which decreases the conductivity. Pairing the substitutional site preference with the magnitude of this decrease demonstrates that the 7-coordinate site is the major contributor to conductivity. The optical band gaps, in contrast, are shown to be site-independent and composition-dependent. After all 7coordinate Sn has been replaced, the continued substitution of Sn results in the formation of a 7-coordinate In antisite or replacement of 6-coordinate Sn, depending on the identity of the d 0 substitute.

Solid‐state nuclear magnetic resonance of spin‐9/2 nuclei 115In and 209Bi in functional inorganic complex oxides

“…The gallium spectra contain a number of overlapping sidebands at moderate MAS rates F I G U R E 5 209 Bi nuclear magnetic resonance (NMR) of (a) BiAlTeO 6 and (b) BiGaTeO 6 . Experimental data in blue, spectral simulations in orange (10)(11)(12)(13)(14)(15)) that are much smaller than the CT linewidths; this problem is alleviated for 71 Ga but not entirely for 69 Ga at 35 kHz MAS (Figure 7). In each case, the features under static and variable MAS rates could be readily simulated with second-order perturbation theory (Table 3).…”

“…[9][10][11] Complex indium-containing oxides are being developed for the next generation of electronic materials. [12][13][14][15][16] Lithium indium oxides have been studied as prospective solid electrolytes for all-solid-state lithium-ion batteries. [17][18][19] Substituted versions of fluorite bismuth oxide (δ-Bi 2 O 3 ) [20][21][22][23] and Aurivillius-type mixed-metal bismuth oxides [20,24,25] host some of the highest known oxygen-ion conductivities.…”

[(Ba19Cl4)(Ga6Si12O42S8)]: a Two-Dimensional Wide-Band-Gap Layered Oxysulfide with Mixed-Anion Chemical Bonding and Photocurrent Response

“…In the structure, there are two crystallographiclly unique Ga atoms of which Ga1 (Wyckoff site: 8g) is coordinated to two O and two S atoms and Ga2 (Wyckoff site: 16h) is linked by three O atoms and one S atom. As such, both heteroligand [GaO 2 S 2 ] and [GaO 3 S] tetrahedra with typical Ga–O (1.792–1.861 Å) − and Ga–S (2.184–2.203 Å) − distances are formed together (Figure a), which is rather uncommon and has never been reported. It is noteworthy that the [GaO 3 S] species is a newly discovered type of [GaO 4– x Q x ] group in Ga-containing oxychalcogenides.…”

LiSc(SeO3)2·xH2O (0 ≤ x ≤ 1): New Selenites Revealing Water Molecule-Driven Extremely High Temperature Single-Crystal-to-Single-Crystal Transformations

“…Functional metal oxides have drawn extensive attention attributable to their wide variety of useful properties such as magnetoresistance, conductivity, thermoelectric properties, ferroelectricity, pyroelectricity, and piezoelectricity. − Most mixed metal oxide materials with extended structures are generally prepared at high temperature and/or high pressure conditions through solid state or solvothermal reactions. Thus, it is often very difficult to design functional oxide materials using similar synthetic methods employed in solution chemistry for molecular compounds.…”