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Updated: Mar 7, 2026
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Structural, Electronic, and Optical Properties of K2Sn3O7 with an Offset Hollandite Structure
Rebecca D McAuliffe1,2, Christopher A Miller1,2, Xiao Zhang1,2
1Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, ‡Department of Mechanical Science and Engineering, and ∥Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
Abstract:
We present the compound K2Sn3O7, a Sn4+-containing oxide with a unique structure type among oxides. The compound is orthorhombic and reminiscent of an offset hollandite, where open channels hold a row of four K+ per channel per cell. UV-visible spectroscopy indicates a wide band gap semiconductor, which is confirmed by first-principles electronic-structure calculations of band structures, densities of states, and optical properties. The continued discovery of new structure types in ternary tin oxides should remain a priority for the identification of prospective ion conductors and transparent conducting compounds.
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