Applied Science and Convergence Technology

The Korean Vacuum Society (한국진공학회)
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Electronic Structure of Ce-doped ZrO2 Film: Study of DFT Calculation and Photoelectron Spectroscopy

  • Jeong, Kwang Sik (Institute of Physics and Applied Physics, Yonsei University) ;
  • Song, Jinho (Institute of Physics and Applied Physics, Yonsei University) ;
  • Lim, Donghyuck (Institute of Physics and Applied Physics, Yonsei University) ;
  • Kim, Hyungsub (School of Materials Science and Engineering, Sungkyunkwan University) ;
  • Cho, Mann-Ho (Institute of Physics and Applied Physics, Yonsei University)
  • Received : 2015.12.31
  • Accepted : 2016.01.19
  • Published : 2016.01.30
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Abstract

In this study, we evaluated the change of electronic structure during redox process in cerium-doped $ZrO_2$ grown by sol gel method. By sol-gel method, we could obtain cerium-doped $ZrO_2$ in high oxygen partial pressure and low temperature. After post annealing process in nitrogen ambient, the film is deoxidized. We used spectroscopic and theoretical methods to analysis change of electronic structure. X-ray absorption spectroscopy (XAS) for O K1-edge and Density Functional Theory (DFT) calculation using VASP code were performed to verify the electronic structure of the film. Also, high resolution x-ray photoelectron spectroscopy (HRXPS) for Ce 3d was carried out to confirm chemical bond of cerium doped $ZrO_2$. Through the investigation of the electronic structure, we verified as followings. (1) During reduction process, binding energy of oxygen is increase. Simultaneously, oxidation state of cerium was change to 4+ to 3+. (2) Cerium 4+ and cerium 3+ states were generated at different energy level. (3) Absorption states in O K edge were mainly originated by Ce 4+ $f_0$ and Ce 3+, while occupied states in valance band were mainly originated from Ce 4+ $f_2$.

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References

  1. Kaapar J, Fornasiero P, and Graziani M. Use of CeO2-based oxides in the three-way catalysis. Catal Today. 50(2) 285-98 (1999).
  2. Hasegawa Y, Imanaka N, and Adachi G-y. Cerium ion conducting solid electrolyte. J Solid State Chem. 171(1-2) 387-90. https://doi.org/10.1016/S0022-4596(02)00218-9
  3. Skorodumova NV, Simak SI, and Lundqvist BI, Abrikosov IA, Johansson B. Quantum Origin of the Oxygen Storage Capability of Ceria. Phys Rev Lett. 89(16) 166601 (2002). https://doi.org/10.1103/PhysRevLett.89.166601
  4. Suda A, Sobukawa H, Suzuki T, Kandori T, Ukyo Y, and Sugiura M. Store and Release of Oxygen of Ceria-Zirconia Solid Solution Synthesized by Solid Phase Reaction at Near Room Temperature. J Ceram Soc Jpn. 109(1267) 177-80 (2001). https://doi.org/10.2109/jcersj.109.1267_177
  5. Sugiura M. Oxygen Storage Materials for Automotive Catalysts: Ceria-Zirconia Solid Solutions. Catal Surv Asia. 7(1) 77-87 (2003). https://doi.org/10.1023/A:1023488709527
  6. Mamontov E, Egami T, Brezny R, Koranne M, and Tyagi S. Lattice Defects and Oxygen Storage Capacity of Nanocrystalline Ceria and Ceria-Zirconia. The Journal of Physical Chemistry B. 104(47) 11110-6 (2000). https://doi.org/10.1021/jp0023011
  7. Lee MS, An C-H, Park K, Choi J-Y, and Kim H. Effect of Y, Gd, Dy, and Ce Doping on the Microstructural and Electrical Properties of Sol-Gel-Deposited $ZrO_2$ Film. J Electrochem Soc. 158(6) G133-G6 (2011). https://doi.org/10.1149/1.3562971
  8. De Groot F and Kotani A. Core level spectroscopy of solids: CRC press; 2008.
  9. Kresse G and Hafner J. Ab initio molecular dynamics for openshell transition metals. Phys Rev B Condens Matter. 48(17) 13115- 8 (1993). https://doi.org/10.1103/PhysRevB.48.13115
  10. Perdew JP, Burke K, and Ernzerhof M. Generalized Gradient Approximation Made Simple. Phys Rev Lett. 77(18) 3865-8 (1996). https://doi.org/10.1103/PhysRevLett.77.3865
  11. Gutowski M, Jaffe JE, Liu C-L, Stoker M, Hegde RI, Rai RS, et al. Thermodynamic Stability of High-K Dielectric Metal Oxides $ZrO_2$ and HfO2 in Contact with Si and SiO2. MRS Online Proceedings Library. 716 null-null (2002).
  12. Jeong KS, Song J, Lim D, Lee MS, Kim H, and Cho M-H. Structural evolution and defect control of yttrium-doped $ZrO_2$ films grown by a sol-gel method. Appl Surf Sci. 320 128-37 (2014). https://doi.org/10.1016/j.apsusc.2014.08.183
  13. Machida M, Kawano T, Eto M, Zhang D, and Ikeue K. Ln Dependence of the Large-Capacity Oxygen Storage/Release Property of Ln Oxysulfate/Oxysulfide Systems. Chem Mater. 19(4) 954-60 (2007). https://doi.org/10.1021/cm062625n
  14. Beche E, Charvin P, Perarnau D, Abanades S, and Flamant G. Ce 3d XPS investigation of cerium oxides and mixed cerium oxide (CexTiyOz). Surf Interface Anal. 40(3-4) 264-7 (2008). https://doi.org/10.1002/sia.2686
  15. Romeo M, Bak K, El Fallah J, Le Normand F, and Hilaire L. XPS Study of the reduction of cerium dioxide. Surf Interface Anal. 20(6) 508-12 (1993). https://doi.org/10.1002/sia.740200604
  16. Burns RG. Mineralogical applications of crystal field theory: Cambridge University Press; 1993.