Catalytic Oxide Materials

The OSC effectiveness of Ce02 can be significantly improved by the addition of Zv02. The preparation procedure for the mixed oxides is important since it affects the surface area, homogeneity and phase formation of the materiaP. Also, it is well known that a high surface area is essential to achieve a high dispersion of active material, i.e. Pt and Rh, on the metal oxide. 

The influence of zirconium on Ce02 has been investigated by Martinez-Arias 

Barium hexaaluminate (BHA) has been prepared by a reverse microemulsion-mediated sol-gel method . Several important preparation parameters were investigated in this work. Nanoparticles with excellent thermal stability could be obtained under optimal preparation conditions when compared to conventional sol-gel derived materials. This stability improvement is believed to occur since crystallization to the desired hexaaluminate phase took place at a relatively low temperature. Furthermore, this material has been tested as a catalyst for methane combustion . The light-olf temperature for 1 vol.% CH4 in air when using pure BHA as catalyst was observed to be 590 °C. This temperature could be lowered to 400 °C by depositing Ce02 on the catalyst. 

Gan et al. have successfully prepared single-phase perovskite-type LaNiOa, La2Cu04 and BaPbOs by the microemulsion technique . Nanosize La-Ni, La-Cu and Ba-Pb oxalates with molar ratios of 1 1,2 1, and 1 1, respectively, could 

Herrig and Hempelmann have prepared BaTiOa, BaZrOs, SrTiOs and SrZrOs perovskites by hydrolysis of the corresponding metal alkoxides in a microemulsion system . A strong relationship between the hydrolysis rate and water content of the microemulsion was reported. 

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Qian, M. and Zeng, H. C. (1997). Synthesis and characterization of Mg-Co catalytic oxide materials for low-temperature N20 decomposition. J. Mater. Chem. 7, 493. 

I 6 Photoelectron Spectroscopy of Catalytic Oxide Materials Table 6.2 XPS binding energy positions of deconvoluted V 2pj/2 peaks of V O /support catalysts from literature... 

I 6 Photoelectron Spectroscopy of Catalytic Oxide Materials Acknowledgments... 

Studies ofCe Redox Behavior in Catalytic Oxide Materials... 

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