TY - JOUR
T1 - Photocatalytic CO2 reduction by Cr-substituted Ba2 (In2-xCrx)O5·(H2O)δ (0.04 ≤ x ≤ 0.60)
AU - Yoon, Songhak
AU - Gaul, Michael
AU - Sharma, Sitansh
AU - Son, Kwanghyo
AU - Hagemann, Hans
AU - Ziegenbalg, Dirk
AU - Schwingenschlögl, Udo
AU - Widenmeyer, Marc
AU - Weidenkaff, Anke
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: The authors wish to express their thanks to Mr. Samir Hammoud for chemical analysis and B.Sc. Maximilian Hackner for UV–visible diffuse reflectance measurements. We also acknowledge Dr. Eberhard Goering for his support with MPMS magnetometry and Mr Cedric Schnyder (Natural History Museum of Geneva) for the additional Raman spectroscopy measurements. Dr. Angelika Veziridis is acknowledged for helpful discussions and comments. This work was financially supported by the Vector Stiftung (project number 2015-044) and the Swiss National Science Foundation (project number 200021_169033/1). The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST).
PY - 2018/2/9
Y1 - 2018/2/9
N2 - Cr-substituted polycrystalline Ba2(In2-xCrx)O5·(H2O)δ powders (0.04 ≤ x ≤ 0.60) were synthesized by solid state reaction to investigate the relation of crystal structure, thermochemical, magnetic, and optical properties. The Cr-substitution results in an unit cell expansion and formation of the higher-symmetric tetragonal phase together with increased oxygen and hydrogen contents. Magnetic property measurements reveal that the diamagnetic pristine Ba2In2O5·(H2O)δ becomes magnetically ordered upon Cr-substitution. By UV–vis spectroscopy a gradual shift of the absorption-edge energy to lower values was observed. Numerical calculations showed that the observed bandgap narrowing was ascribed to the Cr induced states near the Fermi level. The correlation between the changes of crystal chemistry, magnetic, and optical properties of Cr-substituted Ba2(In2-xCrx)O5·(H2O)δ can be explained by the replacement of In by Cr. Consequently, an enhanced photocatalytic CO2 reduction activity was observed with increasing Cr substitution, compatible with the state-of-the-art high surface area TiO2 photocatalyst (P-25).
AB - Cr-substituted polycrystalline Ba2(In2-xCrx)O5·(H2O)δ powders (0.04 ≤ x ≤ 0.60) were synthesized by solid state reaction to investigate the relation of crystal structure, thermochemical, magnetic, and optical properties. The Cr-substitution results in an unit cell expansion and formation of the higher-symmetric tetragonal phase together with increased oxygen and hydrogen contents. Magnetic property measurements reveal that the diamagnetic pristine Ba2In2O5·(H2O)δ becomes magnetically ordered upon Cr-substitution. By UV–vis spectroscopy a gradual shift of the absorption-edge energy to lower values was observed. Numerical calculations showed that the observed bandgap narrowing was ascribed to the Cr induced states near the Fermi level. The correlation between the changes of crystal chemistry, magnetic, and optical properties of Cr-substituted Ba2(In2-xCrx)O5·(H2O)δ can be explained by the replacement of In by Cr. Consequently, an enhanced photocatalytic CO2 reduction activity was observed with increasing Cr substitution, compatible with the state-of-the-art high surface area TiO2 photocatalyst (P-25).
UR - http://hdl.handle.net/10754/627123
UR - http://www.sciencedirect.com/science/article/pii/S1293255817311688
UR - http://www.scopus.com/inward/record.url?scp=85042025490&partnerID=8YFLogxK
U2 - 10.1016/j.solidstatesciences.2018.02.005
DO - 10.1016/j.solidstatesciences.2018.02.005
M3 - Article
SN - 1293-2558
VL - 78
SP - 22
EP - 29
JO - Solid State Sciences
JF - Solid State Sciences
ER -