Effects of H2/O2 and H2/O3 gases on PtMo/C cathode PEMFCs performance operating at different temperatures

This study reported the activity of catalysts synthesized from platinum and molybdenum alloys in different atomic ratios and used as cathode electrocatalysts in the PEMFC. The structural properties of PtMo/C and Pt/C catalysts were analyzed by XRD analysis. The composition and distribution of these alloys in Vulcan XC-72R Carbon were determined by SEM and EDX techniques. CV studies assessed electrochemical properties such as ORR and ECSA activity. The performance of PEMFC cathodes that supplied pure hydrogen and oxygen was examined using polarization curves at different temperatures. Another way to improve the cathodic reaction is to use ozone as a potent oxidizing agent. It was measured that the OCV of the H₂/O₃ PEM fuel cell was 1.60 V, much greater than the open circuit voltage of the traditional H₂/O₂ PEM fuel cell. The PtMo/C catalyst achieved its highest power density of 137 mWcm⁻² at 70 °C, 128 mWcm⁻² at 60 °C, 101 mWcm⁻² at 50 °C, and 85 mWcm⁻² at 40 °C when exposed to H₂/O₂. As the temperature of the cell was raised, it was seen that the catalyst's catalytic activity increased.The maximum power density was detected to be inversely related to the rise in temperature when ozone was used. At low current densities, however, ozone was observed to greatly boost activation polarization.     

Exploring the photocatalytic hydrogen production potential of titania doped with alumina derived from foil waste

The multifunctional potential of a catalyst previously synthesised for thermal processes is explored by investigating its activity for photocatalytic production of H₂ from glycerol, a by-product from the manufacture of bio-diesel. The studied catalyst contains TiO₂ doped with Al₂O₃ that was derived from aluminum foil waste. This catalyst showed higher photocatalytic activity than the analogous catalyst prepared with a commercial Al₂O₃. Pt and Pd act as electron traps while the Al₂O₃ demonstrated a promotional effect, partially through proton donation. Under optimum conditions, a steady-state of 4.2 mmol H₂ gTiO₂⁻¹ hr⁻¹ was produced, which is comparable to the 4.7 mmol H₂ gTiO₂⁻¹ hr⁻¹ obtained with Pt–TiO₂, which is a standard photocatalytic material. It should be noted that the reported Pt/Pd/TiO₂-ANFL catalyst has not yet been optimised and so this result is encouraging. It is hoped that these findings can inspire more sustainable and less expensive hydrogen production, including from biomass feedstocks such as glycerol.     

Turning glycerol surplus into renewable syngas through glycerol steam reforming over a sol-gel Ni–Mo2C-Al2O3 catalyst

In this work, a sol-gel Ni–Mo₂C–Al₂O₃ catalyst is employed for the first time in the glycerol steam reforming for syngas production. Catalyst stability and activity are investigated in the temperature range of 550 °C–700 °C and time on stream up to 30 h. As reaction temperature increases, from 550 °C to 700 °C, H₂ yield boosts from 22% to 60%. The stability test, carried out at milder conditions (600 °C and Gas-Hourly Space-Velocity (GHSV) of 50,000 mL h⁻¹.g_cat⁻¹), shows high catalyst stability, up to 30 h, with final conversion, H₂ yield, and H₂/CO ratio of 95%, 53% and 1.95, respectively. Both virgin and spent catalysts have been characterized by a multitude of techniques, e.g., Atomic-Absorption spectroscopy, Raman spectroscopy, N₂-adsorption-desorption, and Transmission Electron Microscopy (TEM), among others. Regarding the spent catalysts, carbon deposits’ morphology becomes more graphitic as the reaction temperature increases, and the total coke formation is mitigated by increasing reaction temperature and lowering GHSV.     

Large scale synthesis of Mo2C nanoparticle incorporated carbon nanosheet (Mo2C–C) for enhanced hydrogen evolution reaction

Herein, we report the development of a simple, scalable, and cost-effective strategy for the synthesis of 2D sheets of molybdenum carbide and carbon (Mo₂C–C) nanocomposite, by spray drying, as an efficient electrocatalyst. The synthetic methodology contains spray drying of clear aqueous precursor solution mixture of ammonium carbonate, ammonium heptamolybdate, and glucose followed by calcination under N₂ atmosphere. The desired Mo₂C nanoparticle and carbon were synthesized through carbothermal reduction of spray-dried carbonaceous mass, where partially decomposed glucose serves as carbon source. The synthesized Mo₂C–C sheets calcined at an optimized temperature of 800 °C (Mo₂C–C 800) are thin, porous and contain homogeneously dispersed Mo₂C nanoparticles (8–15 nm) in carbon. The Mo₂C–C 800 modified glassy carbon electrode exhibited excellent electrocatalytic activity for hydrogen evolution reaction (HER) with reduced over-potential of 110 mV at 10 mA/cm² (η₁₀) having reduced Tafel slope 69 mV dec⁻¹ in 0.5 M aqueous H₂SO₄ solution. The catalyst also showed long term stability in an acidic as well as in the red-ox environment.     

The effects of alumina morphology and Pt electron property on reversible hydrogenation and dehydrogenation of dibenzyltoluene as a liquid organic hydrogen carrier

The morphologies and the electron property of catalysts play the very important roles in the hydrogenation and dehydrogenation of liquid organic hydrogen carriers (LOHCs) such as dibenzyltoluene (DBT). The different morphologies and pore structures of γ-Al₂O₃ and Mo_xC doped γ-Al₂O₃ were synthesized as the supports for Pt catalysts. After analyzing of various characterizations and catalytic testing, it was found that the large surface area and the mesoporous structure of catalysts are beneficial to both DBT hydrogenation and perhydro-dibenzyltoluene (H18-DBT) dehydrogenation. The doping of Mo_xC promoted the formation of the smaller Pt nanoparticles and increased Pt dispersion. The forming Pt–Mo structure is beneficial to hydrogen spillover which suppress the formation of by-product. The high Pt dispersion of 0.1 wt% Mo_xC doped Pt/Al₂O₃ catalyst plays the positive roles in increasing H18-DBT dehydrogenation activity.     

Two-dimensional Mo2C: An efficient promoter for hydrogen storage and release from a liquid organic hydrogen carrier

Two-dimensional Mo₂C (2D-Mo₂C) is reported for the first time as an effective promoter of a Pt/Al₂O₃ catalyst for both the hydrogenation and dehydrogenation of the liquid organic hydrogen carrier (LOHC) pair, dibenzyltoluene (DBT) and perhydro-dibenzyltoluene (H18-DBT), respectively. Addition of 6.2 wt% 2D-Mo₂C to a Pt/Al₂O₃ catalyst resulted in a significant increase in both the degree of hydrogenation and dehydrogenation compared to the unpromoted catalyst. An analysis of the initial (120 min) perhydro-DBT dehydrogenation kinetics in the temperature range of 270–330 °C, resulted in a reduction in apparent activation energy from 119.5 ± 3.8 kJ/mol for the Pt/Al₂O₃ catalyst to 110.4 ± 5.6 kJ/mol for the 6.2 wt% 2D-Mo₂C/Pt/Al₂O₃ catalyst. The 6.2 wt% 2D-Mo₂C/Pt/Al₂O₃ catalyst was also more stable than the unpromoted catalyst over several consecutive cycles of hydrogenation and dehydrogenation. Catalyst characterization showed that addition of 2D-Mo₂C resulted in an increase in particle size and electron density of the Pt, which enhanced both the hydrogenation and dehydrogenation reactions, despite the fact that the 2D-Mo₂C alone was inactive for both reactions.     

Biomass-derived carbon nanosheets coupled with MoO2/Mo2C electrocatalyst for hydrogen evolution reaction

Transition metal carbide such as molybdenum carbide has been widely used in electrolytic water for hydrogen production due to its potential catalytic property. The synthesis of molybdenum carbide-based high-efficient catalysts by simple process remains great challenges. Herein, Mo oxide/carbide material with hybrid morphology was synthesized by carbonizing mixture of lotus roots and Mo salt. The as-obtained material consists of MoO₂/Mo₂C (MOMC) anchored on biomass-derived nitrogen-doped carbon (NC) matrix. The results show that as-prepared material displays leaf-like and belt-like nanosheets, and the MOMC/NC catalyst with optimal Mo contents exhibits an excellent activity with a low overpotential of 138 mV to drive 10 mA cm^?2 and Tafel slope is 56.7 mV dec^?1 in alkaline medium, indicating that as-prepared catalyst will have promising application in the field of catalysis.     

Selective hydrogen combustion in the presence of propylene and propane over Pt/A-zeolite catalysts

The behavior of selective hydrogen combustion (SHC) in the presence of propylene and propane changing with reaction temperature in a range of 100–600 °C has been investigated over the Pt catalysts supported on A-zeolites. The effect of Pt loading varying from 0.01 to 2 wt% on the catalytic SHC performance has been studied in the conditions with a feed gas molar composition of C₃H₈/C₃H₆/H₂/O₂ = 4/4/4/2 balanced with N₂ and gas hourly space velocity of 15,000 h⁻¹. The results show that for each Pt/3A catalyst having a different Pt loading there is a maximum of H₂ conversion by combustion appearing between 300 and 400 °C, while the selectivity to comprehensive H₂ conversion can maintain 100% when the temperature lower than 300 °C. Moreover, the Pt/3A catalyst with a Pt loading of 0.5 wt % performs better than the others at the temperatures higher than 300 °C. The maximal H₂ combustion achieved over the 0.5 wt% Pt/3A catalyst is as high as 96.6% along with a selectivity of 100% at 300 °C, and a 92.4% H₂ combustion with 98.5% selectivity can be obtained even if at 500 °C. The characterization of the catalysts reveals that the distribution of Pt atoms and the number of atoms in Pt clusters may be the key factors for giving rise to the good SHC performance. The influence of three types of A-zeolite supports on the Pt catalyzed SHC process has also been investigated. 3A zeolite is superior to 4A and 5A for supporting 0.5 wt% Pt catalyst in terms of both activity and selectivity. The lower C₃H₆ conversion on the 0.5 wt% Pt/3A catalyst compared to the 0.5 wt% Pt/5A may be ascribed to the insufficient sites for the C₃H₆ activation on the surface of Pt/3A due to the limitation of 3A channels inaccessible to C₃H_6. This contrarily brings about the better SHC performance on the 0.5 wt% Pt/3A catalyst.     

Autothermal reforming of ethanol on noble metal catalysts

Autothermal reforming of ethanol on zirconia-supported Rh and Pt mono- and bimetallic catalysts (0.5 wt-% total metal loading) was studied as a source of H₂-rich gas for fuel cells. The results were compared with those obtained on a commercial steam reforming catalyst (15 wt-% NiO/Al₂O₃). The Rh-containing catalysts exhibited the highest selectivity for H₂ production and were stable in 24 h experiments. The formation of carbonaceous deposits was lower on the noble metal catalysts than on the commercial NiO/Al₂O₃ catalyst. Thus, the Rh-containing catalysts are more suitable than the commercial NiO/Al₂O₃ catalysts for the ATR of ethanol.     

Biohydrogen production by gas phase reforming of glycerine and ethanol mixtures

In this paper the steam reforming of bioalcohols over Ni and Pt catalysts supported on bare Al₂O₃ and La₂O₃ and CeO₂-modified Al₂O₃ to produce H₂ was studied. Catalytic activity results showed that the glycerine and the intermediate liquid products may hinder the ethanol adsorption on metal active sites of the catalysts, especially at temperatures below 773 K. In fact, ethanol conversion was lower than glycerine conversion in the steam reforming reaction at low temperatures. H₂ chemisorption revealed that La₂O₃ doping of the Ni/Al₂O₃ catalyst improved the metal dispersion providing a better behaviour to the Ni/Al₂O₃-O2 catalyst towards H₂ production. In the case of Pt catalysts, the good reducibility and the H₂ spillover effect provided to the Pt/Al₂O₃-O1 catalyst the capacity to produce higher H₂ yields.     

Hydrogen production through autothermal reforming of CH4: Efficiency and action mode of noble (M = Pt,Pd) and non-noble (M = Re,Mo, Sn) metal additives in the composition of Ni-M/Ce0.5Zr0.5O2/Al2O3 catalysts

Hydrogen production through autothermal reforming of methane (ATR of CH₄) over promoted Ni catalysts was studied. The control of the ability to self-activation and activity of Ni-M/Ce_0.5Zr_0.5O₂/Al₂O₃ catalysts was achieved by tuning their reducibility through the application of different types (M = Pt, Pd, Re, Mo or Sn) and content (molar ratio M/Ni = 0.003, 0.01 or 0.03) of additive. The comparison of the efficiency and action mode of noble (M = Pt, Pd) and non-noble (M = Re, Mo, Sn) metal additives in the composition of Ni-M/Ce_0.5Zr_0.5O₂/Al₂O₃ catalysts was performed using X-ray fluorescence analysis, N₂ adsorption, X-ray diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed reduction with hydrogen, and thermal analysis. The composition-characteristics-activity correlations were determined. It was shown that the introduction of a promoter does not affect the textural and structural properties of catalysts but influences their reducibility and performance in ATR of CH₄. At the similar dispersion of NiO active component (11 ± 2 nm), the Ni²⁺ reduction is intensified in the following order of additives: Mo < Sn < Re ≤ Pd < Pt. It was found that for the activation of Ni and Ni–Sn catalysts before ATR of CH₄ tests, the pre-reduction is required. On the contrary, the introduction of Pt, Pd and Re additives leads to the self-activation of catalysts under the reaction conditions and an increase of the H₂ yield due to the enhanced reducibility of Ni²⁺. The efficient and stable catalyst for hydrogen production has been developed: in ATR of CH₄ at 850 °C over an optimum 10Ni-0.9Re/Ce_0.5Zr_0.5O₂/Al₂O₃ catalyst the H₂ yield of 70% is attained. The designed catalyst has enhanced stability against oxidation and sintering of Ni active component as well as high resistance to coking.     

Study on water–gas shift reaction performance using Pt-based catalysts at high temperatures

The water–gas shift reaction (WGSR) performance was experimentally studied using Pt-based catalysts for temperature, time factor and steam to carbon (S/C) molar ratio at ranges of 750–850 °C, 10–20 g_cat h/mol_CO, and 1–5, respectively. Al₂O₃ spheres were used as the catalyst support. For the high S/C cases, it was found that CO conversion can be enhanced when Pt/CeO₂/Al₂O₃ catalyst was used as compared with Pt/Al₂O₃. For the low S/C ratio cases, CO conversion enhancement was not significant with the addition of CeO₂. It was also found that CO conversion was not influenced by the CeO₂ amount to a large extent. Using bimetallic Pt–Ni/CeO₂/Al₂O₃ catalyst, it was found that higher CO conversion can be obtained as compared with CO conversions obtained from monometallic catalysts (Pt/Al₂O₃ or Pt/CeO₂/Al₂O₃). The experimental data also indicated that good thermal stability can be obtained for the Pt-based catalysts studied.     

PtCo/N-doped carbon sheets derived from a simple pyrolysis of graphene oxide/ZIF-67/H2PtCl6 composites as an efficient catalyst for methanol electro-oxidation

Many alloy catalysts have been developed for methanol electro-oxidation, but most synthetic methods are complicated. Herein, PtCo alloy catalysts supported on N-doped carbon sheets (PtCo/NCS) are successfully prepared by a simple pyrolysis of graphene oxide/ZIF-67/H₂PtCl₆ composites at different temperatures (700, 800, 900 °C) under a gas flow of H₂/Ar, in which ZIF-67 is served as Co and N sources. SEM, TEM, XRD, XPS and electrochemical characterization are employed to study as-prepared catalysts. In acidic methanol solution, the area-specific activity (1.25 mA cm⁻² Pt) of PtCo alloy catalyst obtained at 800 °C (PtCo/NCS-800) is 2.6 times of commercial Pt/C (0.48 mA cm⁻² Pt), and the area-specific activity of PtCo/NCS-800 is 3.5 times of Pt/C after 1000 cycles. Furthermore, an improved CO-tolerance of Pt is confirmed. The electronic effect and synergistic effect of metallic elements are responsible for outstanding performance of as-prepared catalysts. This work provides a simple approach to obtain high performance alloy catalysts.     

Hydrogen-rich syngas production by catalytic cracking of tar in wastewater under supercritical condition

This paper presents the results from experimental study of syngas production by catalytic cracking of tar in wastewater under supercritical condition. Ni/Al₂O₃ catalysts were prepared via the ultrasonic assisted incipient wetness impregnation on activated alumina, and calcined at 600 °C for 4 h. All catalysts showed mesoporous structure with specific surface area in a range of 146.6–215.3 m²/g. The effect of Ni loading (5–30 wt%), reaction temperature (400–500 °C), and tar concentration (0.5–7 wt%) were systematically investigated. The overall reaction efficiency and the gas yields, especially for H₂, were significantly enhanced with an addition of Ni/Al₂O₃ catalysts. With 20%Ni/Al₂O₃, the H₂ yield increased by 146% compared to the non-catalytic experiment. It is noteworthy that the reaction at 450 °C with the addition of 20%Ni/Al₂O₃ had a comparable efficiency to the reaction without catalyst at 500 °C. The maximum H₂ yield of 46.8 mol/kg_tar was achieved with 20%Ni/Al₂O₃ at 500 °C and 0.5 wt% tar concentration. The catalytic performance of the catalysts gradually decreased as the reuse cycle increased, and could be recovered to 88% of the fresh catalyst after regeneration. 20%Ni/Al₂O₃ has a potential to improve H₂ production, as well as a good reusability. Thus, it is considered a promising catalyst for energy conversion of tar in wastewater.     

Reformate gas composition and pressure effect on CO tolerant Pt/Ti0.8Mo0.2O2–C electrocatalyst for PEM fuel cells

Mixed-oxide coated Ti_0.8Mo_0.2O₂–C composite supported 20 wt% Pt electrocatalysts with Ti_0.8Mo_0.2O₂/C=75/25 mass ratio were developed for CO tolerance of polymer electrolyte membrane fuel cell (PEMFC) anode. Studies of the structure, composition and stability, as well as the results of CO_ads stripping confirmed that the mixed oxide composite support and the electrocatalyst prepared for this study show the well-documented characteristics of the Pt/Ti_1-xMo_xO₂-C systems with enhanced CO tolerance compared to the Pt/C catalyst.Dilution of hydrogen with CO₂ and CH₄ had negligible negative impact on the fuel cell performance. Switching gas composition between hydrogen and reformate shows recovery of potential after CO poisoning. Nevertheless, anode catalyst loading of 0.25 and 0.5 mgPt/cm² was not enough to give reasonable performance when CO impurity was present. Loading of 0.85 mgPt/cm² Ti_0.8Mo_0.2O₂–C supported catalyst was effective to give 1000 mA/cm² current density at 0.6 V under 25 ppm CO and 30 psig. Higher loading was needed at mass transfer limited region to overcome poisoning. However, loadings higher than 0.85 mgPt/cm² caused mass transfer limitations. Hence higher loadings is proposed with 40 wt% Pt/Ti_0.8Mo_0.2O₂–C support catalyst.     

On the role of size controlled Pt particles in nanostructured Pt-containing Al2O3 catalysts for partial oxidation of methane

The effect of the Pt loadings and particles sizes on the stability of Pt(x wt%)/Al₂O₃ catalysts were investigated in the partial oxidation of methane (POM) reaction. The Al₂O₃ support was prepared by sol-gel method and different Pt loadings, varying from 0.5 to 2.0 wt% were incorporated to alumina through the incipient wetness impregnation method. The physicochemical features of the catalysts were determined by XRD, ICP-OES, Nitrogen-sorption, UV–Visible, H₂-TPR, CO-DRIFTS, SEM-EDS, XPS and HRTEM techniques. The metal dispersion was evaluated in the cyclohexane dehydrogenation reaction. Lower Pt loadings resulted in well dispersed Pt^o nanoparticles with an enhanced activity in cyclohexane dehydrogenation and POM reactions. With increasing Pt loading to 2.0 wt%, the Pt nanoparticles of the Pt(2.0 wt%)/Al₂O₃ showed a methane conversion of 63% in 24 h of time on stream, and the catalyst was very selective to H₂ and CO. Based on the HRTEM, XPS and Raman spectroscopy techniques, an increment in the Pt loadings evidenced an enrichment of Pt^o clusters on the surface, however, no heavy carbon deposits formation was observed.     

Cyclic voltammetry and X-ray photoelectron spectroscopy studies of electrochemical stability of clean and Pt-modified tungsten and molybdenum carbide (WC and Mo2C) electrocatalysts

The electrochemical stability of tungsten carbide (WC), Pt-modified WC, molybdenum carbide (Mo₂C), and Pt-modified Mo₂C has been examined using an in situ electrochemical half-cell in combination with X-ray photoelectron spectroscopy (XPS). The WC surface, created via the carburization of a tungsten foil, was electrochemically stable to ∼0.8 V with respect to the normal hydrogen electrode (NHE) when exposed to dilute sulfuric acid. At higher potentials, XPS confirmed the surface oxidation of WC to form W_xO_y species. The deposition of submonolayer coverage of Pt on the WC surface increased the region of stability of WC, extending the onset of catalyst oxidation to ∼1.0 V (NHE). These results suggest that both WC and Pt/WC have the potential to be used as anode electrocatalysts. In contrast, both Mo₂C and Pt-modified Mo₂C underwent oxidation at ∼0.4 V (NHE), indicating that molybdenum carbides are not stable enough for applications as anode electrocatalysts.     

Studies on influence of hydrogen and carbon monoxide concentration on reduction progression behavior of molybdenum oxide catalyst

Temperature programmed reduction (TPR) analysis was applied to investigate the chemical reduction progression behavior of molybdenum oxide (MoO₃) catalyst. The composition and morphology of the reduced phases were characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM). The reduction progression of MoO₃ catalyst was attained with different reductant types and concentration (10% H₂/N₂, 10% and 20% CO/N₂ (%, v/v)). Two different modes of reduction process were applied. The first approach of reduction involved non-isothermal mode reduction up to 700 °C, while the second approach of reduction involved the isothermal mode reduction for 60 min at 700 °C. Hydrogen temperature programmed reduction (H₂-TPR) results showed the reduction progression of three-stage reduction of MoO₃ (Mo⁶⁺ → Mo⁵⁺ → Mo⁴⁺ → Mo⁰) with Mo⁵⁺ and Mo⁴⁺. XRD analysis confirmed the formation of Mo₄O₁₁ phase as an intermediate phase followed by MoO₂ phase. After 60 min of isothermal reduction, peaks of metallic molybdenum (Mo) appeared. Whereas, FESEM analysis showed porous crater-like structure on the surface cracks of MoO₂ layer which led to the growth of Mo phase. Meanwhile, the reduction of MoO₃ catalyst in 10% carbon monoxide (CO) showed the formation of unstable intermediate phase of Mo₉O₂₆ at the early stage of reduction. Furthermore, by increasing 20% CO led to the carburization of MoO₂ phase, resulted in the formation of Mo₂C rather than the formation of metallic Mo, as confirmed by XPS analysis. Therefore, the presented study shows that hydrogen gave better reducibility due to smaller molecular size, which contributed to high diffusion rate and achieved deeper penetration into the MoO₃ catalyst compared to carbon monoxide reductant. Hence, the reduction of MoO₃ in carbon monoxide atmosphere promoted the formation of Mo₂C which was in agreement with the thermodynamic assessment.     

Hydrogen production from glycerol dry reforming over Ag-promoted Ni/Al2O3

In recent times, glycerol has been employed as feedstock for the production of syngas (H₂ and CO) with H₂ as its main constituent. This study centers on dry reforming of glycerol over Ag-promoted Ni/Al₂O₃ catalysts. Prior to characterization, the catalysts were synthesized using the wet impregnation method. The reforming process was carried out using a fixed bed reactor at reactor operating conditions; 873–1173 K, carbon dioxide to glycerol ratio of 0.5 and gas hourly space velocity (WHSV) in the range of 14.4 ≤ 72 L g_cat⁻¹ h⁻¹). Ag (3)-Ni/Al₂O₃ gave highest glycerol conversion and hydrogen yield of 40.7% and 32%, respectively. The optimum conditions which gave highest H₂ production, minimized methane production and carbon deposition were reaction temperature of 1073 K and carbon dioxide to glycerol ratio of 1:1. This result can attributed to the small metal crystallite size characteristics possessed by Ag (3)–Ni/Al₂O₃, which enhanced metal dispersion in the catalyst matrix. Characterization of the spent catalyst revealed the formation of two types of carbon species; encapsulating and filamentous carbon which can be oxidized by O₂.     

Preliminary studies of the electrochemical performance of Pt/X@MoO3/C (X = Mo2C,MoO2, Mo) catalysts for the anode of a DMFC: Influence of the Pt loading and Mo-phase

The present study is focused on the influence of Pt loading on the reactivity of catalysts prepared supporting the metal on novel core–shell molybdenum substrates. The electrocatalytic activity and stability of nine Pt/X@MoO3/C catalysts (where X denotes the nature of Mo-phases in the core of the core–shell Mo-particle: Mo₂C, MoO₂ and/or Mo⁰) with three Pt loading (5, 20 and 30 wt% Pt) were tested for carbon monoxide and methanol electro–oxidation reactions.