Effect of Zr4+ doping on the stabilization of ZnCo-mixed oxide spinel system and its catalytic activity towards N2O decomposition

被引：21

作者：

Basahel, S. N. ^{[1
]}

El-Maksod, I. H. Abd ^{[1
]}

Abu-Zied, B. M. ^{[2
]}

Mokhtar, M. ^{[1
]}

机构：

[1] King Abdulaziz Univ, Fac Sci, Dept Chem, Jeddah 21569, Saudi Arabia

[2] Assiut Univ, Fac Sci, Dept Chem, Assiut 71516, Egypt

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2010年 / 493卷 / 1-2期

关键词：

Spinel; Doping; ZnCo2O4; Activation energy; ESR; N2O decomposition; NITROUS-OXIDE; CATION DISTRIBUTION; COBALT; COMBUSTION; SURFACE; CO; BEHAVIOR; TOLUENE; GASES; ZRO2;

D O I：

10.1016/j.jallcom.2009.12.169

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Cobalt-zinc hydroxycarbonate precursor with nominal Co/Zn atomic ratio of 2 and 0.05-0.15 mol% ZrO2-doped precursors have been synthesized from their metal nitrate and sodium carbonate by coprecipitation route. ZnCo2O4 spinel oxide was formed during the precipitation process as complemented by FTIR Decomposition of the Co/Zn precursor at 350 degrees C resulted in the formation of ZnCo2O4 as evidenced by XRD technique. Zr4+-doped samples stabilized the ZnCo2O4 phase and suppressed the formation of ZnO phase at 550 and 750 degrees C. The highest surface areas (S-BET) were attained for the samples doped with 0.15 mol% ZrO2. Activation energy of sintering derived from XRD and S-BET data was directly proportional to the dopant concentration. ESR results revealed that the addition of increased amounts of Zr4+ enhances the formation of Co2+ ions. The activity of the 350 and 750 degrees C calcined catalysts was tested for N2O direct decomposition. The observed activities were related to the presence of Co2+-Co3+ ion pairs which were enhanced by the addition of Zr4+ ions. (C) 2009 Elsevier B.V. All rights reserved.

引用

页码：630 / 635

页数：6

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