수열합성공정에 의한 ZrxCe1−xO2 촉매 분말의 제조 및 특성
Fabrication and characterization of ZrxCe1−xO2 catalytic powder by a hydrothermal process
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초록
세리아 분말은 Ce 이온의 산화, 환원 반응을 통한 산소저장능력(OSC)이 뛰어나 배기가스를 정화하는 자동차의삼원촉매에 대표적인 재료로 사용된다. 그러나 일반적으로 세리아는 고온에서 열적 안정성이 떨어지기 때문에 금속이온을도핑시켜 열적 안정성을 향상시켜 사용한다. 따라서 본 연구에서는 Zr 이온을 세리아 분말에 도핑시켰고, 도핑으로 인해입자크기가 감소하면서 비 표면적 증가로 인해 그 특성은 더욱 향상되었다. 그리고 본 연구에서는 세리아 및 Zr 이온이 도핑된 세리아를 나노 크기로 합성하기 위해 수열반응법을 이용하여 합성하였다. 수열합성 조건은 pH = 11, 반응온도는200 o C에서 6시간 동안 합성하였다. 수열합성법을 이용하여 합성된 세리아 및 Zr 도핑 CeO2 나노 분말의 평균 입자 크기는약 20 nm 이하였다. 합성된 세리아 나노분말의 비표면적은 52.03 m 2 /g, Zr 이온이 도핑된 CeO2 분말의 비 표면적은132.27 m 2 /g이었다.
Abstract
The ceria powder is excellent in oxygen storage capacity (OSC) through the oxidation and reduction reaction of Ce ions and is used as a typical material for a three-way catalyst of an automobile which purifies the exhaust gas. However, since ceria generally has poor thermal stability at high temperatures, it is doped with metal ions to improve thermal stability. Therefore, in this study, Zr ions were doped into ceria powder, and their characteristics were further improved due to the increase of specific surface area with decreasing particle size due to doping. In this study, the synthesis of zirconium doped ceria nanopowder was synthesized by hydrothermal process. In order to synthesis Zr ion doped ceria nanopowder, the precursor reaction at was 200 o C for 6 hours. The average particle size of synthesized Zr doped CeO2 nanopowder was below 20 nm. The specific surface area of synthesized Zr ion doped ceria nanopowder increased from 52.03 m 2 /g to 132.27 m 2 /g with Zr increased 30 %.
참고문헌 (24)
- N. Phonthammachai, "Synthesis and rheological properties of mesoporous nanocrystalline CeO2 via sol-gel process", Colloids Surf. A, 247, pp.61~ (2004)
- L. Liu, "Ceria-supported nickel borate as a sulfur-tolerant catalyst for autothermal reforming of a proxy jet fuel", Catal. Today, 263, pp.52~ (2016)
- L. Ilieva, "NO reduction by CO over gold based on ceria, doped by rare earth metals", Catal. Today, 139, pp.168~ (2008)
- Q. Fu, "Gold-ceria catalysts for low-temperature water-gas shift reaction", Chem. Eng. J., 93, pp.41~ (2003)
- H. C. Yao, "Ceria in automotive exhaust catalysts : 1. oxygen storage", J. Catal., 86, pp.254~ (1984)
- T. Bunluesin, "Studies of the water-gas-shift reaction on ceria-supported Pt, Pd, and Rh: implications for oxygen-storage properties", Appl. Catal. B, 15, pp.107~ (1998)
- G. Panzera, "CO selective oxidation on ceria-supported Au catalysts for fuel cell application", J. Power Sources, 135, pp.177~ (2004)
- A. V. Thorat, "Defect chemistry and vacancy concentration of luminescent europium doped ceria nanoparticles by the solvothermal method", J. Phys. Chem. C, 118, pp.10700~ (2014)
- P. Bera, "Promoting effect of CeO2 in combustion synthesized Pt", CeO2 catalyst for CO oxidation, 2003, pp.107, 6122~
- R. Li, "Synthesis and UV-shielding properties of ZnO- and CaO-doped CeO2 via soft solution chemical process", Solid State Ionics, 151, pp.235~ (2002)
- K. Tanwar, "Synthesis & characterization of Dy and Ca Co-doped ceria based solid electrolytes for IT-SOFCs", J. Alloys Compd., 684, pp.683~ (2016)
- P. Jasinski, "Nanocrystalline undoped ceria oxygen sensor", Sensor Actuator B Chem., 95, pp.73~ (2003)
- O. P. Rodríguez, "Optical properties of ceriazirconia epitaxial films grown from chemical solutions", Mater. Chem. Phys., 138, pp.462~ (2013)
- B. Choudhury, "Ce 3+and oxygen vacancy mediated tuning of structural and optical properties of CeO2 nanoparticles", Mater. Chem. Phys., 131, pp.666~ (2012)
- Z. Fang, "Properties of cerium hydroxides from matrix infrared spectra and electronic structure calculations", Inorg. Chem., 55, pp.1702~ (2016)
- A. G. Macedo, "Catalytic performance of ceria nanorods in liquid-phase oxidations of hydrocarbons with tert-butyl hydroperoxide", Molecules, 15, pp.747~ (2010)
- S. A. Tabrizi, "Optimization of the synthesis parameters of high surface area ceria nanopowder prepared by surfactant assisted precipitation method", Appl. Surf. Sci., 257, pp.10595~ (2011)
- C. M. Y. Yeung, "Comparison of new microemulsion prepared “Pt-in-ceria catalyst with conventional Pt-on-ceria catalyst for water-gas shift reaction", J. Phys. Chem. B, 110, pp.8540~ (2006)
- K. Higashi, "Synthesis and sintering of rare-earth-doped ceria powder by the oxalate coprecipitation method", J. Mater. Res., 14, pp.957~ (1999)
- X. Gao, "The activity and characterization of CeO2-TiO2 catalysts prepared by the sol-gel method for selective catalytic reduction of NO with NH3", J. Hazard. Mater., 174, pp.734~ (2010)
- T. Karaca, "Synthesis of nanocrystalline samarium-doped CeO2 (SDC)powders as a solid electrolyte by using a simple solvothermal route", Ceram. Int., 36, pp.1101~ (2010)
- W. Yuejuan, "Preparation of high-surface area nano- CeO2 by template-assisted precipitation method", J. Rare Earth., 25, pp.58~ (2007)
- H. Wang, "A model to understand the oxygen vacancy formation in Zr-doped CeO2: electrostatic interaction and structural relaxation", J. Phys. Chem., 113, pp.10229~ (2009)
- P. Singh, "Controlled synthesis of nanocrystalline CeO2 and Ce1−xMxO2−d (M = Zr, Y, Ti, Pr and Fe) solid solutions by the hydrothermal method:Structure and oxygen storage capacity", J. Solid State Chem., 181, pp.3248~ (2008)