Designed synthesis of cobalt and its alloys by polyol process

Joseyphus, R. Justin; Matsumoto, Takatoshi; Takahashi, Hideyuki; Kodama, Daisuke; Tohji, Kazuyuki; Jeyadevan, Balachandran

doi:10.1016/j.jssc.2007.07.024

Cited by 107 publications

(72 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In recent years, methodological development of the synthesis of the highly active electrocatalysts has been one of the major topics in energy converting systems [74][75][76][77][78][79]. Joseyphus and co-workers [80] investigated the reaction rate of the polyol method using cobalt and its alloys. The reduction limit of polyol solution depends mainly on the concentration of hydroxyl ions (OH − ) for the reduction of metal ions.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Recent Advances in Carbon Supported Metal Nanoparticles Preparation for Oxygen Reduction Reaction in Low Temperature Fuel Cells

et al. 2015

View full text Add to dashboard Cite

Abstract:The oxygen reduction reaction (ORR) is the oldest studied and most challenging of the electrochemical reactions. Due to its sluggish kinetics, ORR became the major contemporary technological hurdle for electrochemists, as it hampers the commercialization of fuel cell (FC) technologies. Downsizing the metal particles to nanoscale introduces unexpected fundamental modifications compared to the corresponding bulk state. To address these fundamental issues, various synthetic routes have been developed in order to provide more versatile carbon-supported low platinum catalysts. Consequently, the approach of using nanocatalysts may overcome the drawbacks encountered in massive materials for energy conversion. This review paper aims at summarizing the recent important advances in carbon-supported metal nanoparticles preparation from colloidal methods (microemulsion, polyol, impregnation, Bromide Anion Exchange…) as cathode material in low temperature FCs. Special attention is devoted to the correlation of the structure of the nanoparticles and their catalytic properties. The influence of the synthesis method on the electrochemical properties of the resulting catalysts is also discussed. Emphasis on analyzing data from theoretical models to address the intrinsic and specific electrocatalytic properties, depending on the synthetic method, is incorporated throughout. The synthesis process-nanomaterials structure-catalytic activity relationships highlighted herein, provide ample new rational, convenient and OPEN ACCESSCatalysts 2015, 5 311 straightforward strategies and guidelines toward more effective nanomaterials design for energy conversion.

show abstract

Section: Methodsmentioning

confidence: 99%

“…Parameters such as reaction duration, reaction temperature, and the pH value of the electrolyte assist to a remarkable extent the reduction kinetics [63,80].…”

Section: Orr Activity On Various Carbon Supported Nanoparticles Prepamentioning

confidence: 99%

Recent Advances in Carbon Supported Metal Nanoparticles Preparation for Oxygen Reduction Reaction in Low Temperature Fuel Cells

et al. 2015

View full text Add to dashboard Cite

show abstract

“…On the other hand, fine Fe-Co particles have been successfully synthesized by using a polyol process. [8][9][10] In the polyol process, Fe-Co alloy particles are prepared in a poly alcohol such as ethylene glycol (EG), which is used as both solvent and reducing agent to fabricate fine particles from dissolved cations. The solution reaction derived fine Fe-Co alloy particles are prospective to have any useful difference in the property of thermal orderdisorder transformation from the bulk for which it is well known.…”

Section: Introductionmentioning

confidence: 99%

Order-Disorder Transformation in Fe<SUB>50</SUB>Co<SUB>50</SUB> Particles Synthesized by Polyol Process

et al. 2010

Self Cite

View full text Add to dashboard Cite

X-ray diffraction applied anomalous dispersion effect was used for characterizing the order-disorder transformation in Fe 50 Co 50 fine particles synthesized by polyol process. The long range order parameter was estimated from the superlattice peak intensities in the diffraction pattern of particles annealed in the temperature range between 20 and 800 C. The results showed that fine particles of as-synthesized Fe-Co have a disordered structure at room temperature, while the ordered structure is present, to a great extent, in Fe-Co bulk alloys. The fine particles of the disordered alloy were transformed to the ordered state by annealing up to about 450 C. The magnetic properties of the Fe-Co alloy fine particles annealed at different temperatures were also investigated using a vibrating sample magnetometer, in which magnetic fields of up to 15 kOe were applied to samples at room temperature. The saturation magnetization of the as-synthesized particles increased with annealing temperature. This may be attributed to transformation from disordered to ordered structure, along with sintering.

show abstract

“…A similar mechanism can be envisaged for the reduction of Sn 2+ and as the reaction is completed in air, Sn 0 can be easily oxidized to SnO 2 . However, as shown by Joseyphus et al the reduction of metals such as Sn, Ni, Co, Fe, Cr or Mn using the polyol method is more sophisticated; Sn 2+ is almost at the limit of EG reducing power [14], which explains the very low yield obtained for this reaction, being between 5 and 10%. Ng et al proposed a different pathway [10] where SnCl 2 is firstly hydrolyzed to SnOH + and then oxidized to SnO 2 .…”

Section: Resultsmentioning

confidence: 97%

In situ polyol-assisted synthesis of nano-SnO2/carbon composite materials as anodes for lithium-ion batteries

Courtel

Baranova

Abu-Lebdeh

et al. 2010

Journal of Power Sources

View full text Add to dashboard Cite

In situ polyol-assisted synthesis of nano-Sn02/carbon composite materials as anodes for lithium-ion batteries Courtel, Fabrice M.; Baranova, Elena A.; Abu-Lebdeh, Yaser; Davidson, Isobel J.Contact us / Contactez nous: nparc.cisti@nrc-cnrc.gc.ca. Nano-SnO 2 /carbon composite materials were synthesized in situ using the polyol method by oxidizing SnCl 2 ·2H 2 O in the presence of a carbon matrix. All the as-synthesized composites consisted of SnO 2 nanoparticles (5-10 nm) uniformly embedded into the carbon matrix as evidenced by TEM. XRD confirmed the presence of nano-sized SnO 2 particles that are crystallized in a rutile structure and XPS revealed a tin oxidation state of +4. Cyclic voltammetry of the composites showed an irreversible peak at 1.4 V in the first cycle and a typical alloying/de-alloying process at 0.1-0.5 V. The best composite ("composite I", 15 wt% SnO 2 ) showed an improved lithium storage capacity of 370 mAh g −1 at 200 mA g −1 (∼C/2) which correspond to 32% improvement and lower capacity fade compared to commercial SnO 2 (50 nm). We have also investigated the effect of the heating method and we found that the use of a microwave was beneficial in not only shortening reaction time but also in producing smaller SnO 2 particles that are also better dispersed within the carbon matrix which also resulted in higher lithium storage capacity.Crown

show abstract

Designed synthesis of cobalt and its alloys by polyol process

Cited by 107 publications

References 47 publications

Recent Advances in Carbon Supported Metal Nanoparticles Preparation for Oxygen Reduction Reaction in Low Temperature Fuel Cells

Recent Advances in Carbon Supported Metal Nanoparticles Preparation for Oxygen Reduction Reaction in Low Temperature Fuel Cells

Order-Disorder Transformation in Fe<SUB>50</SUB>Co<SUB>50</SUB> Particles Synthesized by Polyol Process

In situ polyol-assisted synthesis of nano-SnO2/carbon composite materials as anodes for lithium-ion batteries

Contact Info

Product

Resources

About