TY - JOUR
T1 - Wurtzite-Derived Quaternary Oxide Semiconductor Cu2ZnGeO4
T2 - Its Structural Characteristics, Optical Properties, and Electronic Structure
AU - Kita, Masao
AU - Suzuki, Issei
AU - Ohashi, Naoki
AU - Omata, Takahisa
N1 - Funding Information:
This work was supported by a Grant-in-Aid for Scientific Research (B) (Grant No. 26289239), a Grant-in-Aid for Scientific Research (A) (Grant No. 17H01315), and a Grant-in-Aid for JSPS Fellows (Grant No. 26763). I.S. has been financially supported by JSPS Overseas Research Fellowships. This work was partly performed under the Cooperative Research Program of the Network Joint Research Center for Materials and Devices (No. 20171069) and Dynamic Alliance for Open Innovation Bridging Human, Environment and Materials.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/11/20
Y1 - 2017/11/20
N2 - The quaternary I2-II-IV-O4 semiconductor, Cu2ZnGeO4, with a wurtz-kesterite structure and 1.4 eV energy band gap has been synthesized for the first time via ion exchange of precursor Na2ZnGeO4. Its crystal structure was refined by Rietveld analysis, and the structural distortion was quantitatively evaluated based on the cation tetrahedral tilting and angle distortion indexes. The tetrahedral distortion in Cu2ZnGeO4 was smaller than in Ag2ZnGeO4 but larger than in β-CuGaO2, suggesting an indirect band gap of Cu2ZnGeO4. Density functional theory calculations using the functional of the local density approximation with corrections for on-site Coulomb interactions indicated that Cu2ZnGeO4 is an indirect semiconductor as expected from its structural feature. However, the energy difference between the direct and indirect band gaps is very small, suggesting that Cu2ZnGeO4 shows strong light absorption near the band edge.
AB - The quaternary I2-II-IV-O4 semiconductor, Cu2ZnGeO4, with a wurtz-kesterite structure and 1.4 eV energy band gap has been synthesized for the first time via ion exchange of precursor Na2ZnGeO4. Its crystal structure was refined by Rietveld analysis, and the structural distortion was quantitatively evaluated based on the cation tetrahedral tilting and angle distortion indexes. The tetrahedral distortion in Cu2ZnGeO4 was smaller than in Ag2ZnGeO4 but larger than in β-CuGaO2, suggesting an indirect band gap of Cu2ZnGeO4. Density functional theory calculations using the functional of the local density approximation with corrections for on-site Coulomb interactions indicated that Cu2ZnGeO4 is an indirect semiconductor as expected from its structural feature. However, the energy difference between the direct and indirect band gaps is very small, suggesting that Cu2ZnGeO4 shows strong light absorption near the band edge.
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U2 - 10.1021/acs.inorgchem.7b02379
DO - 10.1021/acs.inorgchem.7b02379
M3 - Article
C2 - 29083882
AN - SCOPUS:85034643106
SN - 0020-1669
VL - 56
SP - 14277
EP - 14283
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 22
ER -