New palladium alloys catalyst for the oxygen reduction reaction in an acid medium

Savadogo, O.; Lee, K.; Oishi, Kenji; Mitsushima, Shigenori; Kamiya, Noriho; Ota, Ken‐ichiro

doi:10.1016/j.elecom.2003.10.020

Cited by 415 publications

(297 citation statements)

References 8 publications

Supporting

Mentioning

284

Contrasting

Unclassified

Order By: Relevance

“…There is not a clear correlation between C dl or the coefficient m of the CPE with respect to the pore diameter or the DO concentration in PBS. However, the values of C dl per unit area measured on the electrodes in a PBS solution (pH = 7.4) are comparable to the range found in both acid and alkaline media [27,28].…”

Section: Electrochemical Impedance Spectroscopy Studysupporting

confidence: 72%

“…The best value for j 0 = 2.9 × 10 −3 ± 0.5 × 10 −3 µA cm −2 was recorded for the electrodes with 100 nm pores at a DO concentration of 2 ppm. The exchange current density of Pd films deposited by e-beam evaporation is generally similar to that obtained from sputtered Pd films [27].…”

Section: Electrochemical Impedance Spectroscopy Studysupporting

confidence: 66%

“…In contrast, palladium (Pd) possesses some of the same qualities as Pt and is currently used in catalytic converters, fuel cells and hydrogen sensors [26]. Its selective properties towards oxygen reduction have already been explored in acid and alkaline media [20,27,28], where the Pd catalyst was deposited by sputtering, by chemical synthesis or by electrodeposition [27][28][29]. However, the properties towards oxygen reduction of evaporated Pd thin films in neutral physiological solutions (pH = 7.4) has yet to be investigated in detail, especially in the presence of glucose.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Thin film nanoporous electrodes for the selective catalysis of oxygen in abiotically catalysed micro glucose fuel cells

et al. 2016

View full text Add to dashboard Cite

Selective reduction of oxygen is an important property of fuel cells designed to operate in a mixed fuel environment containing both oxidizing and reducing reactants. This would be of particular importance in the design of a long lasting energy supply unit powering implantable microsystems and running from exogeneous chemicals that is abundant in the body (such as glucose and oxygen). This paper presents the development of a nanoporous electrode for oxygen reduction in the presence of glucose. The electrode was fabricated by e-beam deposition of palladium thin films on porous ceramic aluminium oxide (AAO) substrates with a pore size of 100 and 200 nm respectively. The porous nature of the electrodes improved the catalytic properties by increasing the real surface area close to 100 times the geometric surface area. At a dissolved physiological oxygen (DO) concentration of 2 ppm, the maximum exchange current density was found to be 2.9×10 −3 ± 0.5×10 −3 µA cm −2 whereas the potential reduction due to the addition of 5 mM glucose was about 20.6 ± 16.1 mV. The Tafel slopes were measured to be about 60 mV per decade. After running for 21 hours in a physiological saline solution with 2 ppm DO and 3 mM glu- cose, the reduction in the electrode operational potential was -0.13 mV h −1 under a load current density of 4.4 µA cm −2 . These results suggest that nanoporous AAO cathodes coated with palladium offers a reasonable catalytic performance with a good selectivity towards oxygen in the presence of glucose.

show abstract

Section: Electrochemical Impedance Spectroscopy Studysupporting

confidence: 72%

Section: Electrochemical Impedance Spectroscopy Studysupporting

confidence: 66%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Thin film nanoporous electrodes for the selective catalysis of oxygen in abiotically catalysed micro glucose fuel cells

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Savadogo had reported active palladium alloy catalysts without platinum for ORR in acid medium. 5 But the ORR on carbon supported palladium-based alloy in presence of methanol has not been announced hitherto. In this communication, carbon supported palladium-based catalyst as DMFCs cathode was investigated.…”

mentioning

confidence: 99%

An improved palladium-based DMFCs cathode catalyst

Xin

et al. 2004

Chem. Commun.

100

View full text Add to dashboard Cite

A novel carbon-supported palladium-rich Pd 3 Pt 1 /C catalyst prepared by a modified polyol process showed a better cell performance than Pt/C in direct methanol fuel cells, which may be attributed to palladium's inactivity to methanol electro-oxidation while exhibiting good performance to oxygen reduction reaction.There has been growing interest in using direct methanol fuel cells (DMFCs) as transport and portable power sources in recent years. 1 However, polymer electrolyte membranes (PEM) commonly employed, such as Nafion 1 , suffer from high methanol crossover, which not only lowers fuel utilization efficiency but also adversely affects the cathode performance, and thus results in a loss in the overall fuel cell efficiency. One effective way to overcome the crossover problem may be to adopt oxygen reduction selective catalysts for use as the DMFC's cathode. 2 Several transition metal compounds, such as pyrolysed transition metal macrocycles and transition sulfide, have been exploited as methanol-tolerant oxygen reduction reaction (ORR) catalysts 3 because of their good selectivity (y100%) against methanol oxidation reaction (MOR). But the activity of these ORR catalysts was considerably lower than platinum-based ones. Thus, many researchers have been trying to improve DMFCs cathode performance based on platinum catalysts. 4 Li et al obtained good cell performance through adopting multi-walled carbon-nanotube as carbon support; Neergat and his co-workers tried to alloy platinum with transition metal elements such as Co, Cr, Ni and Fe to improve ORR activity; Zhou et al got good DMFCs cathode performance by increasing the mass ratio of platinum metal to carbon support. However, platinum-based catalysts have not been considered ideal DMFCs cathode because of platinum's high intrinsic activity to ORR and MOR. Therefore, it is necessary to find a novel DMFCs cathode catalyst, which has good ORR performance and high selectivity against MOR.Palladium and platinum have very similar properties because they belong to the same group in the periodic table. Savadogo had reported active palladium alloy catalysts without platinum for ORR in acid medium. 5 But the ORR on carbon supported palladium-based alloy in presence of methanol has not been announced hitherto. In this communication, carbon supported palladium-based catalyst as DMFCs cathode was investigated.Pd-Pt/C catalyst with a molar ratio of palladium to platinum of 3 : 1 was prepared by a modified polyol synthesis strategy as described in previous papers. 4d As a comparison, Pt/C was also prepared. The total metal content maintained about 20 wt.% for all the catalysts. Fig. 1 shows the X-ray diffraction (XRD) results of Pd 3 Pt 1 /C and Pt/C. The first peak at the low 2h range (2h # 26u) was associated with the XC-72 carbon support. As displayed in Fig. 1, both the catalysts exhibited the characteristic diffraction fcc. crystalline structure. An angular shift of diffraction peaks to higher positions was found in the XRD pattern of Pd 3 Pt 1 /C as compared to those...

show abstract

“…29,35,[38][39][40][41] Recently carbide based catalysts (e.g., Pt-W 2 C/C, Co 6 Mo 6 C 2 /C) prepared by combining the impregnation and microwave heating methods have been intensively studied. [41][42][43][44] Colloidal method. The major disadvantages of the impregnation method are related to low activity, broad particle size distribution, and tendency to be easily aggregated.…”

Section: Synthesis Methods Of Catalystsmentioning

confidence: 99%

Practical Challenges Associated with Catalyst Development for the Commercialization of Li-air Batteries

Park

Kim

Seo

et al. 2014

Journal of Electrochemical Science and Technology

View full text Add to dashboard Cite

ABSTRACT:Li-air cell is an exotic type of energy storage and conversion device considered to be half battery and half fuel cell. Its successful commercialization highly depends on the timely development of key components. Among these key components, the catalyst (i.e., the core portion of the air electrode) is of critical importance and of the upmost priority. Indeed, it is expected that these catalysts will have a direct and dramatic impact on the Li-air cell's performance by reducing overpotentials, as well as by enhancing the overall capacity and cycle life of Li-air cells. Unfortunately, the technological advancement related to catalysts is sluggish at present. Based on the insights gained from this review, this sluggishness is due to challenges in both the commercialization of the catalyst, and the fundamental studies pertaining to its development. Challenges in the commercialization of the catalyst can be summarized as 1) the identification of superior materials for Li-air cell catalysts, 2) the development of fundamental, material-based assessments for potential catalyst materials, 3) the achievement of a reduction in both cost and time concerning the design of the Li-air cell catalysts. As for the challenges concerning the fundamental studies of Li-air cell catalysts, they are 1) the development of experimental techniques for determining both the nano and micro structure of catalysts, 2) the attainment of both repeatable and verifiable experimental characteristics of catalyst degradation, 3) the development of the predictive capability pertaining to the performance of the catalyst using fundamental material properties. Therefore, under the current circumstances, it is going to be an extremely daunting task to develop appropriate catalysts for the commercialization of Li-air batteries; at least within the foreseeable future. Regardless, nano materials are expected to play a crucial role in this field.

show abstract

New palladium alloys catalyst for the oxygen reduction reaction in an acid medium

Cited by 415 publications

References 8 publications

Thin film nanoporous electrodes for the selective catalysis of oxygen in abiotically catalysed micro glucose fuel cells

Thin film nanoporous electrodes for the selective catalysis of oxygen in abiotically catalysed micro glucose fuel cells

An improved palladium-based DMFCs cathode catalyst

Practical Challenges Associated with Catalyst Development for the Commercialization of Li-air Batteries

Contact Info

Product

Resources

About