Thermal stability of cobalt oxides doped with V2O5 and MoO3

El-Shobaky, G.A.; Ghoneim, N.M.; Hewaidy, I.F.; Morsi, I.M.

doi:10.1016/0040-6031(83)80307-4

Cited by 22 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3 (curve b). Comparing these bands with these predomined by Nyquist and Kagel [20], the two bands assigned at 660 and 560 cm -1 characterizing a Co304 structure [21].…”

Section: Thermal Analysismentioning

confidence: 82%

A study on the thermal decomposition of iron-cobalt mixed hydroxides

Said

El-Salaam

Hassan

et al. 1993

Journal of Thermal Analysis

View full text Add to dashboard Cite

Thermal decomposition of pure Fe(OH)3 and mixed with Co(OH)2 were studied using TG, DTA, kinetics of isothermal decomposition and electrical conductivity measurements. The thermal products were characterized by X-ray diffraction and IR spectroscopy. The TG and DTA analysis revealed the presence of Co 2+ retards the decomposition of ferric hydroxide and the formation of 0~-Fe203. The kinetics of decomposition showed that the mixed samples need higher energy to achieve thermolysis. The investigation of thermal products of mixed samples indicated the formation of cobalt ferrite on addition of x = 1 or 1.5 cobalt hydroxide. The electrical conductivity accompanying the thermal decomposition decreases in presence of low ratio of Co z+ (x = 0.2) via the consumption of holes created during thermal analysis. The continuous increase in t~ values on in-creasing of Co concentration corresponded to the electron hopping between Fe and Co .

show abstract

“…3 (curve b). Comparing these bands with these predomined by Nyquist and Kagel [20], the two bands assigned at 660 and 560 cm -1 characterizing a Co304 structure [21].…”

Section: Thermal Analysismentioning

confidence: 82%

A study on the thermal decomposition of iron-cobalt mixed hydroxides

Said

El-Salaam

Hassan

et al. 1993

Journal of Thermal Analysis

View full text Add to dashboard Cite

show abstract

“…Pure and doped cobalt oxide solids were prepared by the thermal decomposition of pure basic cobalt carbonate (El-Shobaky et al 1980, 1982a and of basic cobalt carbonate treated with different proportions of aluminium nitrate and ammonium molybdate. The doped samples were obtained by treating a known weight of finely powdered basic cobalt carbonate with calculated amounts of AI(NO~)~.9Hp or (NH 4)fiMoP24"4Hp dissolved in the least amount of distilled water to make a paste.…”

Section: Experimental Materialsmentioning

confidence: 99%

Effect of Al₂O₃ and MoO₃ Doping of Co₃O₄ Solid on its Surface and Catalytic Properties

El-Shobaky

Turky

1999

Adsorption Science & Technology

View full text Add to dashboard Cite

Pure and doped COP4 samples were prepared by thermal decomposition at 500-IOOO"C of pure basic cobalt carbonate and of the basic carbonate treated with aluminium nitrate and ammonium molybdate. The amounts of dopants added were varied within the range 0.75-6 mol% Alp, and 0.025-6 mol% MoO,. The influence of this treatment on the specific surface areas and catalytic activities of the COP4 solids was investigated using nitrogen adsorption at -196"C and studies of the decomposition of HPz at 3D-50"C.The results obtained revealed that doping of cobaltic oxide solids with either Alp) or MoO), followed by calcination at 500"C and 700"C, resulted in a progressive increase in the BET surface areas. This increase was, however, more pronounced in the case of MoO) doping. Calcination of the doped solids at 900"C led to an increase in the BET surface areas of the Alp,-treated solids and to a small decrease in the specific surface areas of the MoO,-doped samples.Calcination of the variously doped solids at 500-900"C brought about a decrease in their catalytic activity to an extent proportional to the amount of dopant added. Thus, treatment of COP4 solids with 6 mol% Alp, followed by calcination at 500"C, 700°C and 900°C effected a decrease of 36.9, 42.8 and 67.5% in their activities (expressed as reaction rate constant per unit area) measured at 300c. The decrease in the catalytic activity of COP4 solids due to MoO, doping was greater than that effected by Alp, doping. The doping process did not change the mechanism of the catalytic reaction but effectively decreased the concentration of CO)<--C0 2< ion pairs acting as the active sites involved in the catalytic process.

show abstract

ChemInform Abstract: THERMAL STABILITY OF COBALT OXIDES DOPED WITH VANADIUM PENTOXIDE AND MOLYBDENUM TRIOXIDE

El-Shobaky¹,

Ghoneim²,

Hewaidy³

et al. 1983

Chemischer Informationsdienst

View full text Add to dashboard Cite

show abstract

Thermal stability of cobalt oxides doped with V2O5 and MoO3

Cited by 22 publications

References 11 publications

A study on the thermal decomposition of iron-cobalt mixed hydroxides

A study on the thermal decomposition of iron-cobalt mixed hydroxides

Effect of Al₂O₃ and MoO₃ Doping of Co₃O₄ Solid on its Surface and Catalytic Properties

ChemInform Abstract: THERMAL STABILITY OF COBALT OXIDES DOPED WITH VANADIUM PENTOXIDE AND MOLYBDENUM TRIOXIDE

Contact Info

Product

Resources

About

Thermal stability of cobalt oxides doped with V2O5 and MoO3

Cited by 22 publications

References 11 publications

A study on the thermal decomposition of iron-cobalt mixed hydroxides

A study on the thermal decomposition of iron-cobalt mixed hydroxides

Effect of Al2O3 and MoO3 Doping of Co3O4 Solid on its Surface and Catalytic Properties

ChemInform Abstract: THERMAL STABILITY OF COBALT OXIDES DOPED WITH VANADIUM PENTOXIDE AND MOLYBDENUM TRIOXIDE

Contact Info

Product

Resources

About

Effect of Al₂O₃ and MoO₃ Doping of Co₃O₄ Solid on its Surface and Catalytic Properties