Enhanced Methanol Tolerance of Highly Pd rich Pd-Pt Cathode Electrocatalysts in Direct Methanol Fuel Cells

Choi, Bok Hee; Nam, Woo-Hyun; Chung, Dong Young; Park, In Soo; Yoo, Sung Jong; Song, Jae Chun; Sung, Yung‐Eun

doi:10.1016/j.electacta.2015.02.203

Cited by 49 publications

(20 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our current results are comparable to what has been reported by Choi et al, where a palladium-rich catalyst (Pd 19 Pt 1 /C, 2.8 nm from XRD) shows relatively larger methanol tolerance compared to Pt/C at 70 °C and 6 M methanol concentration. However, the OCP values reported are lower than those achieved in this study [ 34 ]. The same applies to Pd 3 Pt/C (5 nm) catalysts described by Li et al [ 36 ], which were synthesized through a modified polyol method, where OCP values at 1 M methanol concentration and 75 °C are lower compared to those presented here for Pd-based catalysts at the same methanol concentration and 90 °C.…”

Section: Resultscontrasting

confidence: 88%

“…At a low methanol concentration (1 M) and 60 °C, the open circuit potential (OCP) values follow this order: PtC/-AlfaAesar > Pd/C-ETEK > PdFe/C > Pd/C. Under these working conditions, the crossover effects are not so detrimental [ 7 , 9 ]; thus, OCP usually increases when the temperature rises for low methanol concentrations (i.e., 1 M) [ 9 , 33 , 34 ]. However, the methanol permeation rate increases with temperature [ 35 ].…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Carbon-Supported Pd and PdFe Alloy Catalysts for Direct Methanol Fuel Cell Cathodes

et al. 2017

View full text Add to dashboard Cite

Direct methanol fuel cells (DMFCs) are electrochemical devices that efficiently produce electricity and are characterized by a large flexibility for portable applications and high energy density. Methanol crossover is one of the main obstacles for DMFC commercialization, forcing the search for highly electro-active and methanol tolerant cathodes. In the present work, carbon-supported Pd and PdFe catalysts were synthesized using a sodium borohydride reduction method and physico-chemically characterized using transmission electron microscopy (TEM) and X-ray techniques such as photoelectron spectroscopy (XPS), diffraction (XRD) and energy dispersive spectroscopy (EDX). The catalysts were investigated as DMFC cathodes operating at different methanol concentrations (up to 10 M) and temperatures (60 °C and 90 °C). The cell based on PdFe/C cathode presented the best performance, achieving a maximum power density of 37.5 mW·cm−2 at 90 °C with 10 M methanol, higher than supported Pd and Pt commercial catalysts, demonstrating that Fe addition yields structural changes to Pd crystal lattice that reduce the crossover effects in DMFC operation.

show abstract

Section: Resultscontrasting

confidence: 88%

Section: Resultsmentioning

confidence: 99%

Carbon-Supported Pd and PdFe Alloy Catalysts for Direct Methanol Fuel Cell Cathodes

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Accordingly, the cathode is less polarized in the presence of lower methanol permeation. This corresponds to lower overpotentials for the oxygen reduction reaction [ 18 , 19 ]. This strategy is further assisted by using methanol-tolerant cathode electro-catalysts with high activity for oxygen reduction [ 18 , 19 ].…”

Section: Introductionmentioning

confidence: 99%

Selectivity of Direct Methanol Fuel Cell Membranes

et al. 2015

View full text Add to dashboard Cite

Sulfonic acid-functionalized polymer electrolyte membranes alternative to Nafion® were developed. These were hydrocarbon systems, such as blend sulfonated polyetheretherketone (s-PEEK), new generation perfluorosulfonic acid (PFSA) systems, and composite zirconium phosphate–PFSA polymers. The membranes varied in terms of composition, equivalent weight, thickness, and filler and were investigated with regard to their methanol permeation characteristics and proton conductivity for application in direct methanol fuel cells. The behavior of the membrane electrode assemblies (MEA) was investigated in fuel cell with the aim to individuate a correlation between membrane characteristics and their performance in a direct methanol fuel cell (DMFC). The power density of the DMFC at 60 °C increased according to a square root-like function of the membrane selectivity. This was defined as the reciprocal of the product between area specific resistance and crossover. The power density achieved at 60 °C for the most promising s-PEEK-based membrane-electrode assembly (MEA) was higher than the benchmark Nafion® 115-based MEA (77 mW·cm−2 vs. 64 mW·cm−2). This result was due to a lower methanol crossover (47 mA·cm−2 equivalent current density for s-PEEK vs. 120 mA·cm−2 for Nafion® 115 at 60 °C as recorded at OCV with 2 M methanol) and a suitable area specific resistance (0.15 Ohm cm2 for s-PEEK vs. 0.22 Ohm cm2 for Nafion® 115).

show abstract

“…The other intriguing properties identified for using Pd as an alloying element in Pd−Pt catalysts are same crystal structure (FCC) and similar lattice constants (0.77 % mismatch) of Pd and Pt ,. Carbon supported Pd−Co@Pd−Pt catalyst, Pt decorated Pd−Co@Pd core shell structures, Pd−Fe@Pt core shell ORR catalyst with Pd−Fe surface and Pd−Pt core, Pd rich Pd−Pt core shell structures and Pt−Pd/CNT catalyst were projected as methanol tolerant ORR catalysts by various research groups. However, in the presence of methanol, these catalysts display a lower E 1/2 and mass activity values for ORR and methanol oxidation behaviour under RDE experiments.…”

Section: Introductionmentioning

confidence: 99%

Nano-Porous Electro-Catalyst with Textured Surface Active Pd-Pt Islands for Efficient Methanol Tolerant Oxygen Reduction Reaction

Jeyakumar

2017

ChemistrySelect

View full text Add to dashboard Cite

Herein, we report a simple and elegant aqueous synthesis of Pd100‐xPtx (x=5, 10, 15 and 20) nano‐porous structures (NPoS) derived from Pd100‐xMn2x (x=5, 10, 15 and 20) nano‐alloys. Pd100‐xPtx/C NPoS exhibit enhanced oxygen reduction reaction (ORR) activity along with higher retention of figure of merit in the presence of methanol compared to HiSPEC Pt/C catalyst. The ORR mass and specific activity values of Pd100‐xPtx/C NPoS are high and exceed the U.S. department of energy (DOE) 2017–2020 targets. The enhanced methanol tolerance and ORR activity of Pd100‐xPtx/C NPoS is attributed to their unique surface active Pd−Pt islands on nano‐porous Pd. Direct methanol fuel cell performance studies employed using Pd85Pt15/C NPoS as cathode material (0.4 mgPt/cm2) and HiSPEC PtRu/C NPs as anode material (0.2 mgPt/cm2) shows improved direct methanol fuel cell (DMFC) single cell activity at low Pt loading and the results are presented.

show abstract

Enhanced Methanol Tolerance of Highly Pd rich Pd-Pt Cathode Electrocatalysts in Direct Methanol Fuel Cells

Cited by 49 publications

References 53 publications

Carbon-Supported Pd and PdFe Alloy Catalysts for Direct Methanol Fuel Cell Cathodes

Carbon-Supported Pd and PdFe Alloy Catalysts for Direct Methanol Fuel Cell Cathodes

Selectivity of Direct Methanol Fuel Cell Membranes

Nano-Porous Electro-Catalyst with Textured Surface Active Pd-Pt Islands for Efficient Methanol Tolerant Oxygen Reduction Reaction

Contact Info

Product

Resources

About