XRD, HRTEM, magnetic and Mössbauer studies on chemically prepared Fe3+-doped nanoparticles of cerium oxide

Acharya, S.; Bandyopadhyay, A.; Modak, S. S.; Mukherjee, Sudip; Das, Dipankar; Chakrabarti, P.K.

doi:10.1016/j.jmmm.2009.03.071

Cited by 13 publications

(5 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cell parameter for Ce 0.9 Fe 0.1 O 1.97 was calculated to be 0.5389 nm, which is smaller than that of 0.5417 nm for CeO 2 . This finding is consistent with the ionic size difference, 36,37 since Fe 3+ in 8-fold coordination has an ionic size of 0.078 nm, which is smaller than 0.097 for Ce 4+ (oxidation state of Ce and Fe in Ce 0.9 Fe 0.1 O 1.97 were estimated by XPS as shown in Fig. S2 † and Table S1 †).…”

Section: Resultssupporting

confidence: 85%

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Zuo

Huang

et al. 2014

Catal. Sci. Technol.

View full text Add to dashboard Cite

Noble-metal-supported metal oxides (e.g., Au/CeO 2 , Pd/Al 2 O 3 , etc.) are popular as efficient catalysts for many important catalytic reactions, while their high price and easy deactivation restrict their broad application. Herein, we initiate a double substitution methodology to acquire catalysts with merits of excellent catalytic activity, high stability, and relatively low cost. For this purpose, a Au/CeO 2 catalyst was used as reference, and the noble metal Au was completely replaced by the cheaper Ag, meanwhile the rare earth ion, Ce 4+ of the CeO 2 support was partially substituted by the transition metal ion, Fe 3+ . This inversely supported catalyst, Ce 0.9 Fe 0.1 O 1.97 /Ag, was prepared by a two-step method based on co-precipitation and a subsequent liquid-phase reduction. Systematic characterizations demonstrate that Ag nanoparticles with a diameter of around 50 nm were wrapped by Ce 0.9 Fe 0.1 O 1.97 layers. Between the Ag nanoparticles and Ce 0.9 Fe 0.1 O 1.97 layer, there existed a strong interaction. When this sample was tested as a catalyst for CO oxidation, a full conversion temperature of 150 °C was achieved at a space velocity of 24 000 ml h −1 g −1 cat , showing a catalytic activity comparable to that previously reported in the literature on the known catalyst Au@CeO 2 measured at a lower space velocity of 15 000 ml h −1 g −1 cat . More strikingly, this catalyst showed a superb catalytic stability and enhanced oxygen storage capacity. The introduction of smaller Fe 3+ into the CeO 2 lattice and the strong interactions between Ag and Ce 0.9 Fe 0.1 O 1.97 strongly improved the stability and catalytic performance.

show abstract

Section: Resultssupporting

confidence: 85%

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Zuo

Huang

et al. 2014

Catal. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…8. It is observed that the hardness of sintered W-Ag specimens decreases with increase in Ag content from 20.3 to 39.8 wt.%, which could be attributed to the lower hardness value of Ag compared to W [20,21]. This study also show that the hardness values achieved in sintered specimens is higher when compared to other specimens.…”

Section: Vickers Hardness Measurements Of Sintered W-ag Composite Com...supporting

confidence: 53%

Preparation, characterization and densification studies of W-Ag nanocomposites produced by chemical route

Reddy

Krishnaiah

Reddy³

2023

Low-carbon Mater. Green Constr.

View full text Add to dashboard Cite

W-Ag has applications in a wide range of cutting-edge fields, counting heat sinks and microwave absorbers for micro—electronic components, electric arc ends, and filaments for welding processes, electrical contacts, and durable electronic connections. Chemical methods provide a number of benefits, including improved purity, and controlled particle size. The present study focused on the fabrication of W-Ag nano composites using chemical synthesis. W-Ag nanocomposites with average size less than 50 nm were synthesized using Tungsten hexacarbonyl (W(CO)6, and silver acetate (CH3-COOAg) as metal precursors in the present study. The W-Ag composites were sintered using conventional sintering. X-ray diffraction studies of as-prepared powders showed amorphous W-phase and FCC Ag, while sintered W-Ag composites exhibited crystalline BCC W and FCC Ag phase. The effect of sintering temperature on relative density and mechanical properties of W-Ag sintered compacts was investigated. Relative density in excess of 97.6%, 98.2% and 98.8% was achieved for W-20.3 wt.% Ag, W-30.1 wt.% Ag and W-39.8 wt.% Ag composites on conventional sintering at 1000°C for 1 h. Vickers hardness of 364 ± 10 and 320 ± 8 Hv and 279 ± 6 were achieved for W-20.3 wt.% Ag, W-30.1 wt.% Ag and W-39.8 wt.% Ag composite compacts respectively. The hardness value of W-Ag composites decreased with an increase in Ag content. The combination of properties realized in this study renders the composites suitable for automotive and heat sink applications.

show abstract

“…Magnetic susceptibility also showed the presence of α-Fe 2 O 3 , and this was an interesting finding considering that XRD could not confirm the presence of hematite, unlike both of the aforementioned techniques. 291 Iron-doped SnO 2 NPs were prepared with a hydrothermal route by Diamandescu and colleagues. These particles were characterized by electron magnetic resonance (EMR) and Mössbauer spectroscopies.…”

Section: Characterization Methods For Magnetic Nanostructuresmentioning

confidence: 99%

Characterization techniques for nanoparticles: comparison and complementarity upon studying nanoparticle properties

2018

View full text Add to dashboard Cite

Nanostructures have attracted huge interest as a rapidly growing class of materials for many applications. Several techniques have been used to characterize the size, crystal structure, elemental composition and a variety of other physical properties of nanoparticles. In several cases, there are physical properties that can be evaluated by more than one technique. Different strengths and limitations of each technique complicate the choice of the most suitable method, while often a combinatorial characterization approach is needed. In addition, given that the significance of nanoparticles in basic research and applications is constantly increasing, it is necessary that researchers from separate fields overcome the challenges in the reproducible and reliable characterization of nanomaterials, after their synthesis and further process (e.g. annealing) stages. The principal objective of this review is to summarize the present knowledge on the use, advances, advantages and weaknesses of a large number of experimental techniques that are available for the characterization of nanoparticles. Different characterization techniques are classified according to the concept/group of the technique used, the information they can provide, or the materials that they are destined for. We describe the main characteristics of the techniques and their operation principles and we give various examples of their use, presenting them in a comparative mode, when possible, in relation to the property studied in each case.

show abstract

XRD, HRTEM, magnetic and Mössbauer studies on chemically prepared Fe3+-doped nanoparticles of cerium oxide

Cited by 13 publications

References 25 publications

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Preparation, characterization and densification studies of W-Ag nanocomposites produced by chemical route

Characterization techniques for nanoparticles: comparison and complementarity upon studying nanoparticle properties

Contact Info

Product

Resources

About

XRD, HRTEM, magnetic and Mössbauer studies on chemically prepared Fe3+-doped nanoparticles of cerium oxide

Cited by 13 publications

References 25 publications

Ce0.9Fe0.1O1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Ce0.9Fe0.1O1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Preparation, characterization and densification studies of W-Ag nanocomposites produced by chemical route

Characterization techniques for nanoparticles: comparison and complementarity upon studying nanoparticle properties

Contact Info

Product

Resources

About

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation

Ce_0.9Fe_0.1O_1.97/Ag: a cheaper inverse catalyst with excellent oxygen storage capacity and improved activity towards CO oxidation