Effect of Ni on Pt/C and PtSn/C prepared by the Pechini method

Different compositions of Pt, PtNi, PtSn, and PtSnNi electrocatalysts supported on carbon Vulcan XC-72 were prepared through thermal decomposition of polymeric precursors. The nanoparticles were characterized by morphological and structural analyses (XRD, TEM, and EDX). XRD results revealed a face-centered cubic structure for platinum, and there was evidence that Ni and Sn atoms are incorporated into the Pt structure. The electrochemical investigation was carried out in slightly acidic medium (H₂SO₄ 0.05 mol L⁻¹), in the absence and in the presence of ethanol. Addition of Ni to Pt/C and PtSn/C catalysts significantly shifted the onset of ethanol and CO oxidations toward lower potentials, thus enhancing the catalytic activity, especially in the case of the ternary PtSnNi/C composition. Electrolysis of ethanol solutions at 0.4 V vs. RHE allowed for determination of acetaldehyde and acetic acid as the reaction products, as detected by HPLC analysis. Due to the high concentration of ethanol employed in the electrolysis experiments (1.0 mol L⁻¹), no formation of CO₂ was observed.     

Direct ethanol fuel cells based on PtSn anodes: the effect of Sn content on the fuel cell performance

In the present work, several carbon supported PtSn catalysts with different Pt/Sn atomic ratios were synthesized and characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Both the results of TEM and XRD showed that all in-house prepared carbon supported Pt and PtSn catalysts had nanosized particles with narrow size distribution. According to the primary analysis of XPS results, it was confirmed that the main part of Pt of the as-prepared catalysts is in metallic state while the main part of Sn is in oxidized state. The performances of single direct ethanol fuel cells were different from each other with different anode catalysts and at different temperatures. It was found that, the single DEFC employing Pt₃Sn₂/C showed better performance at 60 °C while the direct ethanol fuel cells with Pt₂Sn₁/C and Pt₃Sn₂/C exhibited similar performances at 75 °C. Furthermore, at 90 °C, Pt₂Sn₁/C was identified as a more suitable anode catalyst for direct ethanol fuel cells in terms of the fuel cell maximum power density. Surface oxygen-containing species, lattice parameters and ohmic effects, which are related to the Sn content, are thought as the main factors influencing the catalyst activity and consequently the performance of single direct ethanol fuel cells.     

PtM/C (M = Sn,Ru, Pd,W) based anode direct ethanol–PEMFCs: Structural characteristics and cell performance

In the present work, the role of the structural characteristics of Pt-based catalysts on the single direct ethanol proton exchange membrane fuel cell (PEMFC) performance is examined. Several PtM/C (M = Sn, Ru, Pd, W) catalysts were characterized by means of transmission electron microscopy (TEM) and X-ray diffraction (XRD) and then evaluated as anode catalysts in single direct ethanol fuel cells. XRD spectra showed that Pt lattice parameter decreases with the addition of Ru or Pd and increases with the addition of Sn or W. According to the obtained experimental results, PtSn catalysts presented better electrocatalytic activity towards ethanol electro-oxidation. Based on these results, PtSn/C catalysts with different Pt/Sn atomic ratio were tested and compared. The maximum power density values obtained were correlated with the structural characteristics of the catalysts. A volcano type behaviour between the fuel cell maximum power density and the corresponding atomic percentage of Sn (Sn%) was observed. It was also observed that Sn% affects almost linearly the Pt_xSn_y catalysts’ lattice parameter.     

Effect of addition of rhenium to Pt-based anode catalysts in electro-oxidation of ethanol in direct ethanol PEM fuel cell

Breaking of C–C bond at low temperature to completely oxidize ethanol in direct ethanol fuel cell (DEFC) is the limiting factor for the development of DEFC as alternative source of power in portable electronic equipment. Binary and ternary Pt based catalysts with addition of Re, Pt–Re/C (20:20), Pt–Sn/C (20:20), Pt–Re–Sn/C (20:10:10) and Pt–Re–Sn/C (20:5:15) catalysts were prepared from their precursors by co-impregnation reduction method to study electro-oxidation of ethanol in DEFC. The electrocatalysts characterized by transmission electron microscope, scanning electron microscope, energy dispersive X-ray, and X-ray diffraction shows the formation of above mentioned bi- and tri-metallic catalyst with size ranges from 6 to 16 nm. Electrochemical analyses by cyclic voltammetry, linear sweep voltammetry and chronoamperometry show that Pt–Re–Sn/C (20:5:15) gives higher current density compared to that of Pt–Re/C (20:20) and Pt–Sn/C (20:20). The addition of Re to Pt–Sn/C is conducive to electro-oxidation of ethanol in DEFC. The power density obtained using Pt–Re–Sn/C(20% Pt, 5% Re, 15% Sn by wt) (30.5 mW/cm²) as anode catalyst in DEFC is higher than that for Pt–Re–Sn/C(20% Pt, 10% Re, 10% Sn by wt) (19.8 mW/cm²), Pt–Sn/C (20% Pt, 20% Sn by wt) (22.4 mW/cm²) and Pt–Re/C (20% Pt, 20% Re by wt) (9.8 mW/cm²) at 100 °C, 1 bar, with catalyst loading of 2 mg/cm² and 5 M ethanol as anode feed.     

Pt-based bimetallic catalysts for SO2-depolarized electrolysis reaction in the hybrid sulfur process

SO₂-depolarized electrolysis (SDE) is pivotal in the hybrid sulfur process, which is a promising approach for mass hydrogen production without CO₂ emission. The anode overpotential of SDE is the key component of electrolysis potential. This factor can be reduced by improving anode reaction kinetics. Such improvement is commonly achieved by employing Pt/AC as anode electrode and catalyst, thus also improving economic and electrocatalytic performances. In this work, anode catalysts for SO₂ oxidation reaction are experimentally studied. Platinum-based bimetallic catalysts, including Pt–Pd/C, Pt–Rh/C, Pt–Ru/C, Pt–Ir/C, and Pt–Cr/C, are prepared and characterized. Their electrochemical characteristics for SDE in a once-through mode are investigated in SO₂-saturated 30 wt% sulfuric acid at room temperature by various approaches such as cyclic voltammetry, linear sweep voltammetry, and polarization curves. Results show that 60 wt% Pt–Cr/C exhibits the highest electrocatalytic activity for SDE. Further studies on the metal proportion in Pt–Cr/C show that at a Pt:Cr atomic ratio of 1:2, this bimetallic catalyst demonstrates equal or even better electrolysis performance than 60 wt% Pt/C at a significantly lower economic cost.     

Enhancement of the electrooxidation of ethanol on Pt–Sn–P/C catalysts prepared by chemical deposition process

In this paper, five Pt₃Sn₁/C catalysts have been prepared using three different methods. It was found that phosphorus deposited on the surface of carbon with Pt and Sn when sodium hypophosphite was used as reducing agent by optimization of synthetic conditions such as pH in the synthetic solution and temperature. The deposition of phosphorus should be effective on the size reduction and markedly reduces PtSn nanoparticle size, and raise electrochemical active surface (EAS) area of catalyst and improve the catalytic performance. TEM images show PtSnP nanoparticles are highly dispersed on the carbon surface with average diameters of 2 nm. The optimum composition is Pt₃Sn₁P₂/C (note PtSn/C-3) catalyst in my work. With this composition, it shows very high activity for the electrooxidation of ethanol and exhibit enhanced performance compared with other two Pt₃Sn₁/C catalysts that prepared using ethylene glycol reduction method (note PtSn/C-EG) and borohydride reduction method (note PtSn/-B). The maximum power densities of direct ethanol fuel cell (DEFC) were 61 mW cm⁻² that is 150 and 170% higher than that of the PtSn/C-EG and PtSn/C-B catalyst.     

Ethanol oxidation on Pd/C enhanced by MgO in alkaline medium

The effect of addition MgO to Pd/C catalyst on electrochemical oxidation for ethanol has been studied in alkaline medium. The results show that the reaction activity and the poisoning resistance for ethanol electrooxidation have been significantly improved by addition MgO into Pd/C catalysts. The catalyst with a weight ratio of Pd to MgO of 2:1 gives the best performance. The values of onset potential and peak potential on the Pd–MgO/C electrode are more negative than that on the Pd/C electrode because of synergistic effect between Pd and MgO. By adding MgO to the Pd/C, the value of onset potential negatively shifts more 80 mV and the value of peak current density is 3.4 times higher than that on the Pd/C electrode for ethanol electrooxidation.     

Electrocatalysts supported on multiwalled carbon nanotubes for direct borohydride–hydrogen peroxide fuel cell

Electrocatalysts of Rh, Ru, Pt, Au, Ag, Pd, Ni, and Cu supported on multiwalled carbon nanotubes for direct borohydride–hydrogen peroxide fuel cells are investigated. Metal/γ-Al₂O₃ catalysts for NaBH₄ and H₂O₂ decomposition tests are manufactured and their catalytic activities upon decomposition are compared. Also, the effects of XC-72 and multiwalled carbon nanotube (MWCNT) carbon supports on fuel cell performance are determined. The performance of the catalyst with MWCNTs is better than that of the catalyst with XC-72 owing to a large amount of reduced Pd and the good electrical conductivity of MWCNTs. Finally, the effect of electrodes with various catalysts on fuel cell performance is investigated. Based on test results, Pd (anode) and Au (cathode) are selected as catalysts for the electrodes. When Pd and Au are used together for electrodes, the maximum power density obtained is 170.9 mW/cm² (25 °C).     

Decoration of carbon-supported Pt catalysts with Sn to promote electro-oxidation of ethanol

Carbon-supported Pt/Sn catalysts were prepared by decorating carbon-supported Pt with Sn, by decorating carbon-supported Sn with Pt, and by co-deposition of Pt and Sn on carbon. All of the Pt/Sn catalysts exhibited greatly enhanced activities for ethanol oxidation relative to Pt alone, with the Sn decorated Pt catalyst showing the best performance. The latter catalyst was shown by XPS to contain no metallic Sn, emphasizing the importance of surface Sn oxide species in the activation of Pt for ethanol oxidation. Decoration of Sn with Pt is shown to be a feasible way to increase Pt utilization.     

Electrochemical preparation of Pt-based catalysts on carbon paper treated with Sn sensitization and Pd activation

CoRuPt and CoPtRu catalysts were prepared on carbon paper (CP) using various electrochemical processes including Sn sensitization, Pd activation, Co electrodeposition and galvanic displacement. The Sn-Pd process is a surface treatment that guarantees a larger number of nucleation sites on CP for subsequent Co electrodeposition by modifying the surface to be more hydrophilic. Co particles were deposited on Sn-Pd-treated CP (SCP) by controlling deposition potential and time. Then, Pt and Ru galvanic displacements were performed on the Co particles to form CoRuPt/SCP and CoPtRu/SCP catalysts. Electrochemical measurements confirmed that the CoRuPt/SCP - 1 catalyst with a 1.02 Pt/Ru surface molar ratio showed a peak potential of 741 mV (vs. NHE) for methanol oxidation and 637 mV for carbon monoxide stripping. These values were 80 and 8 mV lower, respectively, than those of a PtRu/C commercial catalyst.     

Preparation, characterization and application of Pt-Ru-Sn/C trimetallic electrocatalysts for ethanol oxidation in direct fuel cell

This work aimed to develop a method for the preparation of carbon-supported platinum nanocatalysts modified with Ruthenium and Tin, which were then evaluated for ethanol eletrooxidation in direct fuel cells. The Pechini method was employed to obtain these catalysts. This method consists in the decomposition of a polymeric precursor of metal salts. Nanocatalysts containing different Pt/Ru/Sn molar ratios were prepared by keeping the carbon/metal ratio at a constant value of 60/40%. The obtained nanoparticles were physico-chemically characterized by X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Energy Dispersive X-ray Spectroscopy (EDX). Crystallite size of around 7.0 nm and 5.8 nm were achieved for the bimetallic and trimetallic nanocatalysts, respectively. The experimental composition was close to the nominal one, but the metal particles were not evenly distributed on the carbon surface. Electrochemical characterization of the nanoparticles was accomplished by cyclic voltammetry (CV) and chronoamperometry. High Performance Liquid Chromatography (HPLC) was carried out after ethanol electrolysis for determining the products generated. Acetaldehyde was the main electrolysis product and traces of CO₂ and acetic acid were also detected. Addition of Ru and Sn to the pure Pt nanoelectrocatalyst significantly improved its performance in ethanol oxidation. The onset potential for ethanol electrooxidation was 0.2 V vs. RHE, in the case of the trimetallic nanocatalyst Pt_0.8Ru_0.1Sn_0.1/C, which was lower than that obtained for the pure Pt catalyst (0.45 V vs. RHE).     

The fabrication of silane modified graphene oxide supported Ni–Co bimetallic electrocatalysts: A catalytic system for superior oxygen reduction in microbial fuel cells

Microbial fuel cells (MFCs) exploit the ability of microorganisms to generate clean energy from organic pollutants in wastewater. However, the poor cathode performance and the use of the expensive rare metal platinum as a catalyst limit their application and scalability. In this study, we have synthesised a Ni–Co/GO nanocomposite and applied it as a potential cathode catalyst to single-chamber MFCs. To improve the performance of a Ni–Co-based hybrid nanocomposite, the support of graphene oxide (GO) is covalently modified with γ-amino propyl tri-ethoxy silane (APTES) through a silane modification reaction. The physical and chemical properties of the synthesised materials are characterised with Fourier transform infrared (FTIR), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) techniques. A microscopic study has shown that metal nanoparticles are distributed uniformly on the MGO matrix. The electrocatalytic activity of the synthesised hybrid nanocatalysts is analysed for oxygen reduction reaction (ORR). A cyclic voltammetry experiment has shown that the Ni–Co/MGO catalyst exhibits a higher reduction peak current value and a higher positive onset potential than the Ni–Co/GO catalyst and Pt/C catalyst, indicating an enhanced ORR activity of the Ni–Co/MGO catalyst. Ni–Co/MGO also exhibits the highest initial current of 0.116 mA in the chronoamperometry test, which decreases to 0.049 mA after 16000 s. The electrochemical results demonstrate that the synthesised Ni–Co/MGO catalyst has a higher electrocatalytic activity and higher stability than the state-of-the-art Pt/C catalyst. More importantly, a MFC with Ni–Co/MGO as a cathode catalyst shows the maximum power density of 1003.18 mWm⁻², which is much higher than in the case of the Ni–Co/GO catalyst (889.6 mWm⁻²) and approximately 2.1 times higher than that of the state-of-the-art Pt/C (483.48 mWm⁻²). Consequently, the Ni–Co/MGO nanocomposite also shows the highest open circuit voltage of 0.857 V among the other studied catalysts. Moreover, the Ni–Co/MGO catalyst has a lower biofouling level than a commercial 10 wt% Pt/C catalyst, which shows that the synthesised cathode catalyst is superior in terms of stability, overall performance and usage. These results suggest that the newly developed Ni–Co/MGO catalyst can be applied as a potential substitute for the Pt/C cathode catalyst for the practical application of MFCs.     

Investigation of ethanol electrooxidation on a Pt–Ru–Ni/C catalyst for a direct ethanol fuel cell

This research is aimed to improve the utilization and activity of anodic alloy catalysts and thus to lower the contents of noble metals and the catalyst loading on anodes for ethanol electrooxidation. The DEFC anodic catalysts, Pt–Ru–Ni/C and Pt–Ru/C, were prepared by a chemical reduction method. Their performances were tested by using a glassy carbon working electrode and cyclic voltammetric curves, chronoamperometric curves and half cell measurement in a solution of 0.5 mol L⁻¹ CH₃CH₂OH and 0.5 mol L⁻¹ H₂SO₄. The composition of the Pt–Ru–Ni and Pt–Ru surface particles were determined by EDAX analysis. The particle size and lattice parameter of the catalysts were determined by means of X-ray diffraction (XRD). XRD analysis showed that both of the catalysts exhibited face centered cubic structures and had smaller lattice parameters than a Pt-alone catalyst. Their particle sizes were small, about 4.5 nm. No significant differences in the ethanol electrooxidation on both electrodes were found using cyclic voltammetry, especially regarding the onset potential for ethanol electrooxidation. The electrochemically active specific areas of the Pt–Ru–Ni/C and Pt–Ru/C catalysts were almost the same. But, the catalytic activity of the Pt–Ru–Ni/C catalyst was higher for ethanol electrooxidation than that of the Pt–Ru/C catalyst. Their tolerance to CO formed as one of the intermediates of ethanol electrooxidation, was better than that of the Pt–Ru/C catalyst.     

Insights on the electrooxidation of ethanol with Pd-based catalysts in alkaline electrolyte

In this work, we report a facile method of synthesis of carbon supported Pd, PdRu, and PdNi nanoparticles, and a comparative study of their catalytic behavior for the electrooxidation of ethanol in alkaline media. The addition of metals such as Ru or Ni increases the oxophilicity of the Pd surface, as observed from the shifting of the Pd oxide reduction peaks. As a consequence, the onset potential for the electrooxidation of ethanol shifts to less positive values on the bimetallic catalysts. The nature and evolution of the species formed during the electrooxidation of ethanol over the catalysts under study has been monitored using in situ infrared spectroscopy. In order to assess properly the evolution of the species formed during the electrooxidation of ethanol, infrared spectra have been recorded in both H₂O and D₂O electrolytes. The results presented in this work demonstrate that the scission of the C–C bond of ethanol takes place at the surface of Pd/C and PdM/C (M = Ni and Ru) at potentials as low as 30 mV. However, at potentials above E ≥ 400 mV, acetates are the main species formed during the electrooxidation of ethanol.     

Catalytic performance of Pd–Ni bimetallic catalyst for glycerol hydrogenolysis

Catalytic conversion of glycerol from biodiesel production to value-added chemicals and fuels is actually of great interest for industrial chemical research. Bimetallic catalysts are confirmed superior to monometallic catalysts in terms of catalytic activity and selectivity for glycerol hydrogenolysis. Accordingly, a series of Pd–M (M = Fe, Co, Ni, Cu, Zn) bimetallic catalysts were prepared in this work via coprecipitation to investigate the promoting effect of Pd. The relationship between the catalytic performance and metal-support interaction was also discussed. Through the catalyst screening, Pd–Ni bimetallic catalyst exhibited moderate activity and the highest selectivity towards ethylene glycol. At 493 K and hydrogen pressure of 6.0 MPa, the glycerol conversion and selectivity of ethylene glycol reached 89% and 22% respectively. XRD and TEM patterns showed that the Pd nanoparticles with an average size of ∼4 nm were uniformly dispersed in the supports. H₂-TPR revealed that the reduction temperatures of metal oxides were significantly decreased by the introduction of Pd component. XPS curves indicated that unique performance of the Pd–Ni bimetallic catalyst might be attributed to the formation of Pd–Ni alloy. And the required metal-support interaction was assumed responsible for the cleavage of C–C bond and generation of ethylene glycol. In the end, hydrogenolysis reactions for the main products of glycerol conversion were carried out over Pd–Ni catalyst to explore the possible reaction pathways for glycerol hydrogenolysis.     

Electrooxidation of CO and methanol on well-characterized carbon supported PtxSn electrodes. Effect of crystal structure

The role of two intermetallic phases of PtSn, namely Pt₃Sn (fcc phase) and PtSn (hcp phase) for the electrooxidation of CO and methanol has been evaluated. Carbon supported Pt₃Sn and PtSn nanosized particles have been prepared by controlled surface reactions. The actual structure of the PtSn alloys has been evaluated and confirmed by means of XRD and HR-TEM studies which reveal the predominance of either the hcp or the fcc phase in each catalyst. The catalysts have been further characterized to identify the actual metal loading and Pt/Sn atomic ratio in order to eliminate particle size or metal loading effects on their electrocatalytic performance. The performance of the catalysts for the electrooxidation of CO and methanol has been evaluated by electrochemical techniques along with in situ techniques such as electrochemical coupled Infrared Reflection Absorption Spectroscopy (EC-IRAS) and differential electrochemical mass spectrometry (DEMS). Altogether, the results presented in this work reveal that Pt₃Sn fcc is more active than PtSn hcp for the electrooxidation of CO and methanol and that the contribution of the hcp phase in those electrocatalytic processes is negligible.     

Electrocatalytic properties of carbon-supported Pt-Ru catalysts with the high alloying degree for formic acid electrooxidation

A series of carbon-supported bimetallic Pt-Ru catalysts with high alloying degree and different Pt/Ru atomic ratio have been prepared by a chemical reduction method in the H₂O/ethanol/tetrahydrofuran (THF) mixture solvent. The structural and electronic properties of catalysts are characterized using X-ray reflection (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM). The electrooxidation of formic acid on these Pt-Ru nanoparticles are investigated by using cyclic voltammetry, chronoamperometry and CO-stripping measurements. The results of electrochemical measurements illustrate that the alloying degree and Pt/Ru atomic ratio of Pt-Ru catalyst play an important role in the electrocatalytic activity of the Pt-Ru/C catalyst for formic acid electrooxidation due to the bifunctional mechanism and the electronic effect. Since formic acid is an intermediate in the methanol electrooxidation on Pt electrode in acidic electrolyte, the observation provides an additional fundamental understanding of the structure-activity relationship of Pt-Ru catalyst for methanol electrooxidation.     

Pd decorated Co–Ni nanowires as a highly efficient catalyst for direct ethanol fuel cells

The storage and conversion of energy necessitates the use of appropriate electrochemical systems and chemical reaction catalysts. This work presents newly developed catalysts for electrooxidation of ethanol in an alkaline medium. Nanocatalysts composed of Co–Ni nanowires (Co–Ni NWs) decorated with Pd nanoparticles (Pd NPs) were made at varying metal ratios and their chemical composition and structure was investigated in detail. The synthesis involved a wet chemical reduction assisted by a magnetic field, which led to the generation of NWs, followed by the deposition of spherical Pd NPs on their surface. The best catalytic activity was obtained for the catalyst made of Co₃–Ni₇ decorated with Pd NPs, which exhibited EOR of 8003 mA/mg_Pd for only 0.86 wt% of Pd loading. The results can be explained by the synergistic effect between the morphology of the bimetallic support and the favorable interaction of oxophilic Co, Ni with catalytic Pd.     

CNT-based catalysts for H2 production by ethanol reforming

Hydrogen production by steam reforming of ethanol (SRE) was studied using steam-to-ethanol ratio of 3:1, between the temperature range of 150–450 °C over metal and metal oxide nanoparticle catalysts (Ni, Co, Pt and Rh) supported on carbon nanotubes (CNTs) and compared to a commercial catalyst (Ni/Al₂O₃). The aim was to find out the suitability of CNTs supports with metal nanoparticles for the SRE reactions at low temperatures. The idea to develop CNT-based catalysts that have high selectivity for H₂ is one of the driving forces for this study. The catalytic performance was evaluated in terms of ethanol conversion, product gas composition, hydrogen yield and selectivity to hydrogen. The Co/CNT and Ni/CNT catalysts were found to have the highest activity and selectivity towards hydrogen formation among the catalysts studied. Almost complete ethanol conversion is achieved over the Ni/CNT catalyst at 400 °C. The highest hydrogen yield of 2.5 is, however, obtained over the Co/CNT catalyst at 450 °C. The formation of CO and CH₄ was very low over the Co/CNT catalyst compared to all the other tested catalysts. The Pt and Rh CNT-based catalysts were found to have low activity and selectivity in the SRE reaction. Hydrogen production via steam reforming of ethanol at low temperatures using especially Co/CNT catalyst has thus potential in the future in e.g. the fuel cell applications.     

High performance direct ethanol fuel cell with double-layered anode catalyst layer

Double-layered anode catalyst layers with two reverse configurations, which consist of 45 wt.% Pt₃Sn/C and PtRu black catalyst layers, were fabricated to improve the performance of a direct ethanol fuel cell (DEFC). The in-house 45 wt.% Pt₃Sn/C catalyst was characterized by XRD and TEM. The cross-sectional double-layered anode catalyst layer was observed by SEM. In DEFC performance test and anode linear sweep voltammetry measurement, the anode with double-layered catalyst layer exhibited better catalytic activity for ethanol electro-oxidation than those with single-layered 45 wt.% Pt₃Sn/C and PtRu black catalyst layers. In terms of anode product distribution, the DEFC with double-layered anode catalyst layer showed a higher yield of acetic acid than that with single-layered PtRu black catalyst layer and a higher yield of CO₂ than that with single-layered 45 wt.% Pt₃Sn/C catalyst layer, respectively. These results suggest that the double-layered anode catalyst layer possessed the advantages of both Pt₃Sn/C and PtRu black catalysts for ethanol electro-oxidation, and thus showed a higher ethanol electro-oxidation efficiency and DEFC performance in the practical polarization potential region.