Direct Methanol Fuel Cell Cathode Research Articles

Regulating local coordination environment of Mg−Co single atom catalyst for improved direct methanol fuel cell cathode

Fuel cells operated with a reformate fuel such as methanol are promising power systems for portable electronic devices due to their high safety, high energy density and low pollutant emissions. However, several critical issues including methanol crossover effect, CO-tolerance electrode and efficient oxygen reduction electrocatalyst with low or non-platinum usage have to be addressed before the direct methanol fuel cells (DMFCs) become commercially available for industrial application. Here, we report a highly active and selective Mg−Co dual-site oxygen reduction reaction (ORR) single atom catalyst (SAC) with porous N-doped carbon as the substrate. The catalyst exhibits a commercial Pt/C-comparable half-wave potential of 0.806 V (versus the reversible hydrogen electrode) in acid media with good stability. Furthermore, practical DMFCs test achieves a peak power density of over 200 mW cm−2 that far exceeds that of commercial Pt/C counterpart (82 mW cm−2). Particularly, the Mg−Co DMFC system runs over 10 h with negligible current loss under 10 M concentration methanol work condition. Experimental results and theoretical calculations reveal that the N atom coordinated by Mg and Co atom exhibits an unconventional d-band-ditto localized p-band and can promote the dissociation of the key intermediate *OOH into *O and *OH, which accounts for the near unity selective 4e− ORR reaction pathway and enhanced ORR activity. In contrast, the N atom in SACCo remains inert in the absorption and desorption of *OOH and *OH. This local coordination environment regulation strategy around active sites may promote rational design of high-performance and durable fuel cell cathode electrocatalysts.

Advances in platinum-based and platinum-free oxygen reduction reaction catalysts for cathodes in direct methanol fuel cells.

Direct methanol fuel cells (DMFCs) have been the focus of future research because of their simple structure, abundant fuel sources, high energy conversion efficiency and low cost. Among the components in DMFC, the activity and stability of the cathode catalyst is the key to the performance and lifetime of the DMFCs. Oxygen reduction reaction (ORR) is an important electrode reaction on DMFC cathode. It is known that Pt is widely used in the fabrication of ORR catalysts, but the limited earth storage of Pt and its high price limit the use of Pt-based commercial catalysts in DMFCs. To overcome these problems, advances have been made on new low Pt-based catalysts and Pt-free catalysts in recent years. In this article, the development of novel ORR catalysts and the carbon supports is reviewed and discussed.

Study of Ruthenium Contamination Effect on Oxygen Reduction Activity of Platinum-Based PEMFC and DMFC Cathode Catalyst

Proton exchange membrane fuel cells (PEMFC) and PEM-based direct methanol fuel cells (DMFC) are promising energy sources for vehicular, stationary and portable applications. While PEMFC-based power systems have already reached a limited commercialization level, durability remains to be one of the main obstacles on the path towards their broad commercialization. One of the degradation mechanisms reducing durability of reformate-based PEMFC and DMFC is ruthenium contamination of the cathode catalyst [i] following ruthenium dissolution from the anode PtRu catalyst and its cross-over to the cathode [ii].The aim of our research is to quantitatively measure the effect of ruthenium contamination on the oxygen reduction reaction (ORR) activity of a typical cathode catalyst. For this purpose, various and precisely known amounts of ruthenium (equivalent to 0.15-4 ruthenium monolayers) were deposited on a commercial 50%Pt/C catalyst (Johnson Matthey HiSPEC8000) using electroless reduction method. The obtained Ru-contaminated Pt/C catalysts were examined using TGA, SEM-EDS, XPS, HR-TEM and STEM-EDS to determine their composition, particles size distribution and structure. Cyclic-voltammetry with rotating–disk–electrode was used to quantitatively determine the effect of ruthenium contamination on the ORR specific activity.It was found that ORR activity exhibits a pseudo-exponential decay with increased ruthenium coverage. At a contamination level of 0.15 equivalent ruthenium monolayer (EDS %at Ru3Pt97, XPS %at Ru7Pt93) a massive, ~45%, decrease in ORR specific activity was measured. At a contamination level of 1 equivalent ruthenium monolayer (EDS %at Ru27Pt73, XPS %at Pt50Ru50) almost a complete inhibition of ORR activity was observed. Ruthenium deposition on platinum in the form of bi-layer islands and 3d-clusters and deactivation of platinum atoms surrounding ruthenium deposition sites were proposed as a possible explanation for the pseudo-exponential decay of the ORR activity. The obtained results allowed us to estimate the decrease in power density of reformate-based PEMFC and DMFC due to ruthenium contamination by 0.15 equivalent monolayer at roughly 10%.Assuming that the decrease in ORR activity is originating from the strong O and OH binding to ruthenium, DFT-calculated O and OH binding energies to ruthenium and platinum were used to estimate ORR activity on model Run/Pt(111) surfaces that represent Ru-contaminated Pt/C catalyst. The estimated ORR activities have shown a dependence on ruthenium contamination that was qualitatively similar to experimental results, indicating that the strong O and OH binding to ruthenium have indeed a negative effect on the ORR activity.[i] L. Gancs, B. N. Hult, N. Hakim, S. Mukerjee, Electrochem. Solid-State Lett., 2007, 10, 9, B150[ii] P. Piela, C. Eickes, E. Brosha, F. Garzon, P. Zelenay, Journal of The Electrochemical Society, 2004, 151 (12), A2053–A2059

Stable, Active, and Methanol-Tolerant PGM-Free Surfaces in an Acidic Medium: Electron Tunneling at Play in Pt/FeNC Hybrid Catalysts for Direct Methanol Fuel Cell Cathodes

PGM-free catalysts have high initial activity for O2 reduction reaction, but they suffer from low stability in acid medium in proton exchange membrane fuel cells (PEMFC) and direct methanol fuel ce...

High‐Performance Direct Methanol Fuel Cells with PGM‐Free Cathode

Direct methanol fuel cells (DMFCs) hold great promise for applications ranging from portable power for electronics to transportation. However, apart from the high costs, current Pt‐based cathodes in DMFCs suffer significantly from performance loss due to severe methanol crossover from anode to cathode. The migrated methanol in cathodes tends to contaminate Pt active sites through yielding a mixed potential region resulting from oxygen reduction reaction and methanol oxidation reaction. Therefore, highly methanol‐tolerant cathodes must be developed before DMFC technologies become viable. The newly developed MOF‐based Fe‐N‐C cathode exhibits high methanol tolerance and exceeds the performance of current Pt cathodes, as evidenced by both rotating disk electrode and DMFC tests. In addition to the highly oxygen-reduction active atomically dispersed FeN4 sites, the unique morphology of MOF-derived carbon in Fe‐N‐C cathodes provides a more unique porous structure. DMFC tests with various methanol concentrations are systematically studied using the best performing Fe‐N‐C catalyst. At feed concentrations greater than 2.0 M, the obtained DMFC performance from the Fe‐N‐C cathode is found to start exceeding that of a Pt/C cathode. This work will open a new avenue to use PGM-free cathode for advanced DMFC technologies with increased performance and at significantly reduced cost.

Hollow PtCu octahedral nanoalloys: Efficient bifunctional electrocatalysts towards oxygen reduction reaction and methanol oxidation reaction by regulating near-surface composition

In response to the scarcity of precious metals, the development of precious-metal-saving electrocatalysts exhibiting high mass activity (MA) and durability towards oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) for both proton-exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) has aroused increasing attention. In this study, octahedral Cu-rich PtCu alloy is seeded to fabricate near-surface composition-tunable PtCu hollow octahedral nanoparticles (HONs) with the wall thickness of ~2.1 nm. Due to both the alloying effects of near surface and the special hollow octahedral structure, the PtCu/C HONs exhibit significantly higher MA and durability than commercial Pt/C towards both ORR in alkaline medium and MOR in sulfuric acid electrolyte. The ORR MA of Pt44.1Cu55.9/C HONs are up to 2.60 A mgPt−1 that is 18.5-fold enhancement compared with that of Pt/C. Besides, after 10,000 voltage cycles, the MA of Pt44.1Cu55.9/C HONs remains to be 1.61 A mgPt−1, a datum 53.7 times that of Pt/C. The in situ CO polarization curves exhibit that the Pt44.1Cu55.9 HONs/C own high resistance to CO poisoning. For MOR in sulfuric acid electrolyte, the optimum SA/MA of PtCu/C HONs is 5.33 mA cm−2/1.94 A mgPt−1, which is 10.25/5.87 times higher than that of Pt/C. This study provides effective bifunctional cathode and anode electrocatalysts for both PEMFCs and DMFCs.

Quantifying the Effect of Ruthenium Contamination on the ORR Activity of DMFC Cathode Catalyst

Direct methanol fuel cell (DMFC) technology is a promising energy source for portable, stationary and light transportation applications in the range of several watts and up to a few kW. Currently, one of the main drawbacks preventing widespread commercialization of DMFCs is their relatively short lifetime, up to a few thousands of hours at best. Usually a DMFC lifetime is not defined by a complete failure of the cell but by a slow and continuous degradation of the performance, up to the point when the delivered power is too low for the intended application. Several different degradation mechanisms contribute to this degradation [i], one of them is ruthenium contamination of the cathode catalyst [ii] following ruthenium dissolution from the anode PtRu catalyst and its cross-over to the cathode [iii]. The aim of our research is to quantitatively measure the effect of ruthenium contamination on the ORR performance of the cathode catalyst. For this purpose, different amounts of ruthenium (equivalent of 0.15-3 monolayers) were deposited on commercial Pt/C nanopowder to simulate ruthenium deposition on the cathode during a DMFC operation. The ruthenium-contaminated Pt/C powders were prepared using electroless polyol reduction method with methanol as the reducing agent. Johnson Matthey HiSPEC 8000 50%Pt/C was chosen to simulate a DMFC cathode catalyst. The composition, particles size and structure of these RuPt/C powders were verified by TGA, SEM-EDS, XPS, HR-TEM and STEM-EDS. Electrochemical characterization was performed with the use of cyclic-voltammetry and rotating–disk–electrode (RDE) techniques and compared to that of HiSPEC 8000. It was found that already at 0.25 equivalent monolayer of ruthenium (EDS %At Pt92Ru8, XPS %At Pt90Ru10) there is a massive, more that 25%, decrease in ORR specific activity of the commercial Pt/C catalyst. This decrease grows rapidly up to a complete inhibition of ORR at approximately 1 equivalent monolayer of ruthenium (EDS %At Pt64Ru36, XPS %At Pt50Ru50). The obtained results quantitatively show that ruthenium contamination indeed has a major role in the performance degradation of DMFCs. [i] A. Mehmood, M. A. Scibioh, J. Prabhuram, M. G. An, H.Y. Ha, Journal of Power Sources, 2015, 297,224–241 [ii] L. Gancs, B. N. Hult, N. Hakim, S. Mukerjee, Electrochem. Solid-State Lett., 2007, 10, 9, B150 [iii] P. Piela, C. Eickes, E. Brosha, F. Garzon, P. Zelenay, Journal of The Electrochemical Society, 2004, 151 (12), A2053–A2059

Catalysis for Low-Temperature Fuel Cells

Today, the development of active and stable catalysts still represents a challenge to be overcome in the research field of low-temperature fuel cells.[...]

An ordered structured cathode based on vertically aligned Pt nanotubes for ultra-low Pt loading passive direct methanol fuel cells

Ordered nanostructured cathodes based on controlled vertically aligned Pt nanotubes are fabricated via combining sacrificial template method and in-situ galvanic replacement for ultra-low Pt loading passive direct methanol fuel cells (DMFCs). The Pt nanotubes are composed of highly dispersed Pt nanoparticles shell with an average thickness of ca. 15nm. Employed as the oxygen reduction reaction (ORR) electrocatalyst, it exhibits similar activity but better durability than that of the commercial Pt black. Serving as the cathode for passive DMFC, a high electrochemical specific area of 77.48m2g−1(Pt) is obtained by the ordered nanostructured cathode, which is 3 times higher than that of the conventional Pt/C based cathode (19.46m2g−1(Pt)), indicating a significant improvement in the Pt catalyst utilization. Impressively, the Pt loading at the cathode side can be reduced to approximately 1/7 (0.12 mgcm−2) of the conventional MEA without sacrificing cell performance by using the vertically aligned Pt nanotubes catalytic layer. This method may provide a new way to fabricate ordered nanostructured cathode for ultra-low Pt loadings fuel cells.

Highly active robust oxide solid solution electro-catalysts for oxygen reduction reaction for proton exchange membrane fuel cell and direct methanol fuel cell cathodes

The identification and development of novel non-noble metals based electro-catalyst exhibiting excellent electrochemical activity and stability than noble metal electro-catalyst is important for commercial development of proton exchange membrane fuel cells (PEMFCs). Such non-noble electro-catalyst with unique electronic structure and superior electrochemical performance will immensely contribute to lowering the capital cost of PEMFCs. Herein, we have identified solid solution electro-catalysts of WO3 and IrO2 for oxygen reduction reaction (ORR) in PEMFCs exploiting theoretical first principles approaches. The theoretical results were experimentally validated by generation of nanostructured (W1-xIrx)Oy (x = 0.2, 0.3; y = 2.7–2.8) electro-catalysts for ORR. (W0.7Ir0.3)Oy demonstrated ∼43% improved electrochemical activity than Pt/C with similar loading at 0.9 V (vs RHE), respectively. Moreover, single full cell PEMFC study revealed an acceptable ∼81% improved maximum power density for (W0.7Ir0.3)Oy than Pt/C combined with excellent long term stability. These results thus, show the potential of (W0.7Ir0.3)Oy as ORR electro-catalyst for replacing of Pt/C in PEMFCs and direct methanol fuel cells on the additional grounds of superior methanol tolerance.

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

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.

Characterization of Pt supported on commercial fluorinated carbon as cathode catalysts for Polymer Electrolyte Membrane Fuel Cell

Pt nanoparticles supported on carbon monofluoride (CFx), synthesized from H2PtCl6 using NaHB4 as a reducing agent has been investigated as a cathode electrocatalyst in fuel cells. Surface characterization, performed by transmission electron microscopy (TEM) and powder X-ray diffraction (PXRD), shows a homogeneous distribution and high dispersion of metal particles. Kinetic parameters for the electrocatalyst are also obtained from the steady state measurements using a rotating disk electrode (RDE) in 0.5 M H2SO4 solution. Analysis by Koutecky–Levich equation indicates an overall 4 e− oxygen reduction reaction (ORR). Evaluation of the catalyst in single cell membrane electrode assemblies (MEAs) for proton exchange membrane based Direct Methanol Fuel Cell (DMFC) and H2 Fuel Cell at different temperatures and flows of O2 and Air are shown and compared against commercial Pt/C as the cathode electrocatalyst. Evaluation of Pt/CFx in H2 fed fuel cells shows a comparable performance against a commercial catalyst having a higher platinum loading. However, in direct methanol fuel cell cathodes, an improved performance is observed at low O2 and air flows showing up to 60–70% increase in the peak power density at very low flows (60 mL min−1).

A hierarchical cathode catalyst layer architecture for improving the performance of direct methanol fuel cell

We report the fabrication of a hierarchical cathode catalyst layer (CL) for application in direct methanol fuel cells (DMFCs). The hierarchical CL, comprised of Pt black as the inner layer and Pt/C as the outer layer, has appropriate structural properties for DMFC cathode. The inner CL with compact structure decreases the CL thickness and prevent Pt sites from methanol contamination, and the cathode outer CL with porous structure increase the electrochemical active surface area. Consequently, the hierarchical cathode CL is able to offset the adverse effect of methanol crossover on the cathode performance by enhancing the Pt catalyst utilization for oxygen reduction reactions (ORR). Therefore, the newly developed membrane electrode assembly (MEA) can maintain the high ORR activity of the cathode catalysts despite the methanol crossover. At a high methanol concentration (3M), it shows high maximum power density (0.156Wcm−2) despite only 1.0mgcm−2 of Pt in the cathode CL.

Investigation of mesoporous carbon hollow spheres as catalyst support in DMFC cathode

In conventional low temperature PEM fuel cells, catalyst activity and stability rely on adequate structure and morphology of carbon support material, especially at the cathode that is exposed to high potential values. Degree of graphitization as well as pore distribution are decisive parameters for corrosion resistivity, catalyst utilization and mass transport. In this work, hollow graphitized carbon spheres (HGS) with mesoporous structure were tested as catalyst support in middle temperature (90–110°C) direct methanol fuel cell (DMFC) cathode. Influence of catalyst loading and concentration as well as working temperature on power density was studied in a 5cm2 laboratory cell. Best results in terms of MEA performance were achieved with a catalyst loading of 2mgPtcm−2 at both electrodes and an extremely dense Pt concentration on carbon support of 50 and 40wt% at the anode and cathode, respectively at 110°C. Additionally, thermal pretreatment of carbon-supported catalyst up to 850°C led to increase in particle size up to 7nm and as a consequence to substantial higher ECSA retention during accelerated degradation test (ADT) under half-cell conditions.

Controllable fabrication of ordered Pt nanorod array as catalytic electrode for passive direct methanol fuel cells

The nanostructure of the catalytic electrode has a great effect on the performance of direct methanol fuel cells (DMFCs), including catalyst utilization, precious metal loading, water balance, and oxygen mass transfer. In this work, ordered arrays of platinum nanorods with different diameters were directly grown onto microporous layers by electrodeposition via a sacrificial template, and were used as the catalytic cathode for passive DMFCs. The use of these ordered electrodes led to a dramatic decrease in cathode polarization behavior. The maximum power density of passive DMFCs fabricated with catalytic electrodes of 200 and 100 nm Pt nanorod arrays were 17.3 and 12.0 mW/cm2, respectively. The obtained improvement in performance was ascribed to the fact that the ordered nanostructured electrode not only increased the electrochemically active surface area and the catalyst utilization, but also enhanced oxygen mass transfer and water balance in the system.

Performance analysis of Fe–N–C catalyst for DMFC cathodes: Effect of water saturation in the cathodic catalyst layer

Iron phthalocyanine (FePc) was used as iron/nitrogen/carbon source and templated with an ordered mesoporous silica (SBA-15), followed by heat treatment and leaching of SiO2 with hydrofluoric acid (sacrificial method). The Fe–N–C catalyst was tested for the oxygen reduction reaction using a rotating disk electrode (three electrode configuration) in the presence of methanol at different concentrations. Furthermore, the catalyst was investigated in a single cell configuration of a direct methanol fuel cell (DMFC) under different methanol concentrations and temperatures. The optimal operating condition was found to be 1 M at 110 °C, reaching 11.2 mW cm−2 using a commercial Pt-Ru black at the anode and the Fe–N–C at the cathode side. Interestingly, the cathodic catalyst was not dramatically affected by the presence of crossovered methanol, showing only a 12% drop in maximum power density with the highest methanol concentration of 10 M at the anode. A 3D multiphysics model was implemented to further explain the experimental DMFC performance data using a commercial platform (Comsol® Multiphysics v4.4a). The model agreed with the experimental data, showing a direct relationship between water saturation, and oxygen consumption, consequently oxygen starvation at the cathodic catalytic layer. The model considered two phases on the cathode side computed by extended Darcy law within the catalytic layer and the gas diffusion layer domains.

High-Performance Direct Methanol Fuel Cells with Precious-Metal-Free Cathode.

Direct methanol fuel cells (DMFCs) hold great promise for applications ranging from portable power for electronics to transportation. However, apart from the high costs, current Pt‐based cathodes in DMFCs suffer significantly from performance loss due to severe methanol crossover from anode to cathode. The migrated methanol in cathodes tends to contaminate Pt active sites through yielding a mixed potential region resulting from oxygen reduction reaction and methanol oxidation reaction. Therefore, highly methanol‐tolerant cathodes must be developed before DMFC technologies become viable. The newly developed reduced graphene oxide (rGO)‐based Fe‐N‐C cathode exhibits high methanol tolerance and exceeds the performance of current Pt cathodes, as evidenced by both rotating disk electrode and DMFC tests. While the morphology of 2D rGO is largely preserved, the resulting Fe‐N‐rGO catalyst provides a more unique porous structure. DMFC tests with various methanol concentrations are systematically studied using the best performing Fe‐N‐rGO catalyst. At feed concentrations greater than 2.0 m, the obtained DMFC performance from the Fe‐N‐rGO cathode is found to start exceeding that of a Pt/C cathode. This work will open a new avenue to use nonprecious metal cathode for advanced DMFC technologies with increased performance and at significantly reduced cost.

A simple preparation of very high methanol tolerant cathode electrocatalyst for direct methanol fuel cell based on polymer-coated carbon nanotube/platinum

The development of a durable and methanol tolerant electrocatalyst with a high oxygen reduction reaction activity is highly important for the cathode side of direct methanol fuel cells. Here, we describe a simple and novel methodology to fabricate a practically applicable electrocatalyst with a high methanol tolerance based on poly[2,2′-(2,6-pyridine)-5,5′-bibenzimidazole]-wrapped multi-walled carbon nanotubes, on which Pt nanoparticles have been deposited, then coated with poly(vinylphosphonic acid) (PVPA). The polymer coated electrocatalyst showed an ~3.3 times higher oxygen reduction reaction activity compared to that of the commercial CB/Pt and methanol tolerance in the presence of methanol to the electrolyte due to a 50% decreased methanol adsorption on the Pt after coating with the PVPA. Meanwhile, the peroxide generation of the PVPA coated electrocatalyst was as low as 0.8% with 2 M methanol added to the electrolyte, which was much lower than those of the non-PVPA-coated electrocatalyst (7.5%) and conventional CB/Pt (20.5%). Such a high methanol tolerance is very important for the design of a direct methanol fuel cell cathode electrocatalyst with a high performance.

Searching for suitable catalysts for a passive direct methanol fuel cell cathode

Trimetallic PtMRu/C cathode catalysts with M = Co or Fe obtained by an impregnation procedure using ethylene glycol and NaBH4 as reducing agent, with suitable activity for the oxygen reduction reaction (ORR) and improved tolerance to methanol, have been physically characterized by HRTEM, EDS and XPS. The examined nanoparticles have a small particle size and are well spread on the carbon support. Pt is mainly found as Pt(0) and Co, Fe and Ru are mostly oxidized. To study their durability and performance for ORR and methanol tolerance over time, the catalysts were subjected to an electrochemical accelerated stress test (AST), consisting in cycling the potential 2000 times. Polarization curves for ORR with and without methanol were recorded. After the AST the trimetallic PtMRu/C catalysts are able to keep their performance for ORR in the presence of methanol.

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

Methanol crossover critically restricts the practical application of direct methanol fuel cells (DMFCs). To resolve this crucial difficulty from the standpoint of electrocatalysis, an electrode material having high activity for the oxygen reduction reaction and low activity for the methanol oxidation reaction compared to widely used Pt-based electrodes is needed for DMFC cathodes. In this research carbon-supported Pd-rich Pd–Pt bimetallic nanoparticle electrocatalysts with 60wt.% metal content were prepared for this purpose by sodium borohydride reduction of metal chlorides. The physical features of the prepared nanoparticles were investigated by transmission electron microscopy, energy dispersive X-ray spectroscopy, atomic absorption spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and X-ray absorption near edge spectroscopy. Methanol tolerance was tested by means of rotating disk electrode (RDE) voltammetry using oxygen-saturated methanol-containing electrolyte solutions as the anode fuel for DMFC unit cell performance tests. In the RDE measurements, Pd-rich electrocatalysts (carbon-supported Pd19Pt1 nanoparticles) showed excellent methanol tolerance compared with Pd-free Pt electrocatalyst. When Pd19Pt1 nanoparticles were used as a DMFC cathode catalyst, unit cell performance tests showed that the i-V curves of the Pd19Pt1 electrocatalyst decreased slightly with increasing methanol concentration, while that of the Pt electrocatalyst decreased rapidly. The results in a liquid-feed DMFC unit cell test were in good agreement with the methanol tolerant characteristics identified in the RDE measurements.