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For practical applications such as fuel cells, it is important to exploit electrocatalysis with high activity for methanol and glycerol oxidation. A platinum nanostructured electrode (PtNPs) is modified by gold adatoms and is created by application of a square wave potential regime to a tantalum surface electrode. In nanostructured platinum, the structure and the surface properties are characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and cyclic voltammetry (CV). In acid and alkaline media, the CV and Chronoamperometric (CA) are studied to investigate the catalytic activity of the PtNPs nanoparticles for the electrooxidation of methanol and glycerol. The prepared nanostructured platinum on a tantalum electrode was allowed to balance an open circuit with a 1.0×10 -3 M solution containing an Au ion. Consequently, the proximity of the irreversibly adsorbed Au-adatoms on the already described Pt-nanostructured electrode. In acidic and alkaline solutions, the electrocatalytically activities toward methanol and glycerol oxidation were evaluated and is found to strongly on the surface of the gold-modified PtNPs. The PtNPs modified by Au electrode system used direct methanol fuel cell (DMFC) and direct glycerol fuel cell (DGFC). The DMFC and DGFC are much higher than in acid output in alkaline. Comparison of the i-E curves of nanostructure platinum electrode with that of a platinum nanostructure electrode modified by Au under similar conditions for the letter, the charge under the peak (i-E curve) in the oxidation region was higher. Furthermore, rough chronoamperometric measurements confirmed the results. The results of showed that the electrocatalytic properties of the nanostructured prepared surface were enhanced by the inclusion of gold adatoms with a variable extent of advancement. The current peak (I p ) and the current chronoamperometric (I CA ) of glycerol oxidation on the PtNPs electrode modified by Au in acid media (130 mA/cm 2 , 47 µA/cm 2 ) were higher than those of the bare PtNPs electrode and in alkaline media (171 mA/cm 2 , 66 µA/cm 2 ). The stronger catalytic behavior in alkaline media of the Au-PtNP electrode indicates its promising use in alkaline direct alcohol cells.

Methanol oxidation reaction (MOR) is used to provide electrical energy via direct methanol fuel cell (DMFC), which requires a practical design of electrocatalysts to accelerate the sluggish MOR. In this study, we successfully fabricated the carbon black nanoparticles/graphite ceramic electrode (CBNPs/GCE) supported metal-organic frameworks (MOFs) and decorated with nickel nanoparticles (NiNPs) as a new type nanocomposite modified electrode (NiNPs/MOFs/CBNPs/GCE) via a chemical and an electrochemical process, respectively. The surface morphology and structure of the synthesized nanocomposite materials and modified electrodes were characterized using field emission scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. Then, the NiNPs/MOFs/CBNPs/GCE was used as a non-platinum electrocatalyst for electrocatalytic oxidation of methanol in alkaline media. The obtained results show the efficient electrocatalytic activity of the NiNPs/MOFs/CBNPs/GCE toward the MOR with high anodic peak current density (J pa = 34.8 mA cm−2) compared with the other prepared electrocatalysts; MOFs/CCE, NiNPs/CCE, MOFs/CBNPs/GCE, NiNPs/CBNPs/GCE, and NiNPs/MOFs/CCE, due to the synergistic effect of nanocomposite components; NiNPs, MOFs and CBNPs. The prepared electrocatalyst; NiNPs/MOFs/CBNPs/GCE, not only shows a high electrochemically active surface area (ECSA = 2.15 cm2) but also has long-term durability in MOR. In general, it can be said the NiNPs/MOFs/CBNPs/GCE is a promising candidate for application in DMFC. The preparation of the new type nanocomposite, construction processes of the NiNPs/MOFs/CBNPs/GCE and its application in MOR. [Display omitted] • The present MOFs was synthesized by a simple and rapid solvothermal method. • The dropped MOFs at the surface of CBNPs/GCE was decorated with NiNPs to fabricate the NiNPs/MOFs/CBNPs/GCE. • The synthesized nanocomposite and modified electrodes were characterized by the appropriated methods. • The NiNPs/MOFs/CBNPs/GCE was used as a potent electrocatalyst for MOR in alkaline media. • The NiNPs/MOFs/CBNPs/GCE displayed enhanced electrocatalytic activity toward MOR with high stability and durability. [ABSTRACT FROM AUTHOR]

PdM/RGN (M = Co, Cu) self-supporting composite electrodes were synthesized via a simple two-step spontaneous reduction process using Ni foam as the substrate and reduced graphene oxide as support layer. The composites were characterized using X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. Cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy were performed to study the electrocatalytic activities of the prepared electrodes for methanol and ethanol oxidation. The performances of PdM/RGN for methanol and ethanol oxidation increased and then decreased as the atomic ratio of Pd to M (Co, Cu) increased. The Pd 6 Co 1 /RGN and Pd 6 Cu 1 /RGN electrodes exhibited markedly superior catalytic activity and long-term stability. The peak current densities of Pd 6 Cu 1 /RGN and Pd 6 Co 1 /RGN electrodes reached 0.36 and 0.29 A/cm2 for methanol electrooxidation and which reached 0.8 and 0.5 A/cm2 for the ethanol electrooxidation, respectively. This excellent performance is owing to the three-dimensional structure of nickel foam, the improving specific surface area and the synergistic effect between Pd and M. [Display omitted] • The electrode manufacture process is facile, green, low energy consumption and binder-free. • Three-dimensional graphene substrate support resulted in excellent stability of PdM/RGN (Co,Cu). • Good synergy in PdM nanoparticles promotes electron transport and increases surface area. • The PdM/RGN (Co,Cu)electrode exhibitshigh catalytic performance for MOR and EOR. [ABSTRACT FROM AUTHOR]

For direct methanol fuel cells, developing low‐cost, highly efficient, and long‐term stable electrocatalysts is crucial. In this work, we report easy and single‐step electrodeposition of nickel sulfide thin film incorporating carbon nanofibers on indium tin oxide (denoted as Ni4S3‐CNF/ITO). The electrodeposited materials were characterized by X‐ray Diffraction, Scanning Electron Microscopy, and Energy Dispersive X‐ray spectroscopy. The electrocatalytic activity toward Methanol Oxidation Reaction (MOR) was investigated using Cyclic Voltammetry, Chrono‐Amperometry, and Electrochemical Impedance Spectroscopy. The electrocatalyst exhibited good electrocatalytic activity regarding methanol electrooxidation in an alkaline medium with retention of its activity over a significant period of time. These results indicate that the incorporation of carbon nanofibers into nickel sulfide allows the electrocatalyst to gain higher surface area and high tolerance to the catalyst‐poising species generated during MOR. The electrocatalytic activity of electrodeposited Ni4S3‐CNF/ITO makes it a promising electrocatalyst for low‐cost, high‐efficient fuel cells. [ABSTRACT FROM AUTHOR]

Direct methanol fuel cells (DMFCs), as an important alternative energy source for portable devices, have attracted considerable interest because of the high energy density of methanol, the simplicity of processing it as a fuel, and the suitability of storage as a liquid fuel. Nevertheless, fuel cell catalysts suffer from strong adsorption of CO on platinum, which leads to poison on the catalyst's surface and the prevention of further oxidation of methanol. Improvements are needed in terms of lowering the number of precious metals required for large-scale applications. Carbon powder, carbon nanotubes, and conducting polymer matrix are shown to have high electrocatalytic performance. Consequently, platinum loading has been diminished pointedly with improved Pt utilization. In this sense, particularly in the current study, the electrooxidation of methanol was investigated on Pt, Ru, and metal oxide nanoparticles such as V2O5 and WO3, modified by polyaniline (PANI)-functionalized multi-wall carbon nanotubes (fCNTs) composite electrodes in terms of DMFCs and related applications. Only electrochemical techniques were utilized throughout the synthesis of electrodes. The citrate method was utilized for preparing all of the metal and metal oxide nanoparticles. A comparative study was realized in each step of the experimental study. It was seen that ternary alloy nanosized electrodes showed much more activity than those of mono or bimetallic systems. The prepared electrodes were viewed and analyzed by SEM, EDX, Raman, and TEM techniques. Moreover, kinetic studies were carried out to determine important parameters. As a concluding remark, the current research presents a highly feasible procedure to produce PANI–fCNTs/Pt–Ru–metal oxide nanoparticle composite materials. [ABSTRACT FROM AUTHOR]

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Studies of methanol electrooxidation reactions have achieved considerable advancements in the recent years for their encouraging contributions in the exciting fields of energy conversion and storage, organic syntheses, wastewater treatment, sensing, medicinal and environmental analyses, and many others thriving fields of modern technology. Accordingly, the fabrication of less expensive, efficient and decent quality electrocatalysts with high material stability, faster electro‐oxidation kinetics, as well as less carbonation and decent corrosion inhibition activities are highly urged. Consequently, scientists around the globe are in continuous search for alternative economical smart anode‐nanocatalysts for methanol oxidations with superior electrochemical performances. In the recent years, various inexpensive and readily‐available nanocatalysts of non‐noble metals like Ni, Co, Cu, etc., in reference to electrooxidation of organic molecules have been reported. The present work highlights the recent progress accomplished by rapidly flourishing nickel‐based electrocatalysts for electrooxidation of methanol. The discussion comprehensively includes the basic mechanistic understandings and fundamentals for achieving high efficacy of methanol electrooxidation with nickel‐based electrocatalysts. Also, the current challenges faced in this emerging area have been outlined to achieve superior, productive, and commercially viable catalysts for methanol electrooxidation in the near future. [ABSTRACT FROM AUTHOR]

In order to find out electrocatalysts based on non-precious metals, Ni–Co/GO-TiO 2 composite with different amounts of nickel and cobalt is prepared and the impacts of TiO 2 nanoparticles on GO support are highlighted. Composition, morphology and textural features of the synthesized materials are characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, N 2 adsorption-desorption isotherms and field emission scanning electron microscopy equipped with energy-dispersive X-ray analysis. The electrochemical activity of the prepared catalysts toward methanol and ethanol electrooxidation in alkaline media is investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry. Results confirmed that adding TiO 2 nanoparticles to graphene oxide can increase the surface area, porosity and electrochemically active surface area of the support material. The composition with the equal amount of nickel and cobalt precursors exhibited the highest current density for methanol and ethanol electrooxiation equal to 121.07 and 145.28 mA/cm2, respectively. Stability test results demonstrated that this sample maintains 94.1% and 87.5% of initial current density after 7200 s for the electrooxidation of ethanol and methanol in 1.0 M KOH, respectively. All results confirm the synergic effect of Ni and Co for the alcohols oxidation in alkaline media and equal amount of Ni and Co leads to the best catalytic performance with the highest current density, lowest impedance and maximum stability. [Display omitted] • GO-TiO 2 was synthesized using a reflux method as support for fuel cell's catalyst. • Ni-Co was deposited on GO-TiO 2 in chemical reduction method. • The electrochemical properties of samples with various amounts of Ni-Co investigated. • Ni-Co/GO-TiO 2 used as electrocatalyst for the alcohol electrooxidation. • The results showed that Ni-Co/GO-TiO 2 has high current density and low impedance. [ABSTRACT FROM AUTHOR]

In this work, three nanoparticle samples, Ni4Co2Pt/CNFs, Ni5CoPt/CNFs and Ni6Pt/CNFs, were designed according to the molar ratio during loading on carbon nanofibers (CNFs) using electrospinning and carbonization at 900 °C for 7 h in an argon atmosphere. The metal loading and carbon ratio were fixed at 20 and 80 wt%, respectively. Various analysis tools were used to investigate the chemical composition, structural, morphological, and electrochemical (EC) properties. For samples with varying Co%, the carbonization process reduces the fiber diameter of the obtained electrospun nanofibers from 200–580 nm to 150–200 nm. The EDX mapping revealed that nickel, platinum, and cobalt were evenly and uniformly incorporated into the carbonized PVANFs. The prepared Ni-Co-Pt/CNFs have a face-centered cubic (FCC) structure with slightly increased crystallite size as the Co% decreased. The electrocatalytic properties of the samples were investigated for ethanol, methanol and urea electrooxidation. Using cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance measurements, the catalytic performance and electrode stability were investigated as a function of electrolyte concentration, scan rate, and reaction time. When Co is added to Ni, the activation energy required for the electrooxidation reaction decreases and the electrode stability increases. In 1.5 M methanol, the Ni5CoPt/CNFs electrode showed the lowest onset potential and the highest current density (30.6 A/g). This current density is reduced to 28.2 and 21.2 A/g for 1.5 M ethanol and 0.33 M urea, respectively. The electrooxidation of ethanol, methanol, and urea using our electrocatalysts is a combination of kinetic/diffusion control limiting reactions. This research provided a unique approach to developing an efficient Ni-Co-Pt-based electrooxidation catalyst for ethanol, methanol and urea.

The solution combustion synthesis was used for preparation of porous CeO 2 with two different fuels; glucose and citric acid, for combustion. The samples of porous CeO 2 are labeled as PCO Glu and PCO Cit. The surface area of PCO Cit and PCO Glu were estimated as 44.50 ± 0.12, and 47.72 ± 0.16 m2 g−1, respectively. The cavities acidity, OH groups on surface, and its bond strength to the active cerium sites are compared by measuring the p H of zero charges; that it was 11.95 ± 0.02, and 11.90 ± 0.03 for PCO Cit and PCO Glu , respectively. The nanosized palladium (NPd) was loaded on PCO Glu and PCO Cit via wetness incorporation. As-prepared nano-microstructure electrocatalysts are utilized in the electrooxidation of C1 compounds, including methanol, formaldehyde, and formic acid. The NPd-PCO Glu presents higher electrocatalytic activity, stability and CO-tolerance ability for the electrooxidation of C1 compounds as compared to the NPd-PCO Cit and NPd as non-supported palladium; So that, the performance of the modified electrodes increase in the order of NPd < NPd-PCO Cit < NPd-PCO Glu. The PCO with porous structural network affected on the electrochemical surface area, dispersion, and durability of NPd. It is effective the capability of removing the poisoning species of the electrooxidation of C1 compounds on NPd through the lattice oxygen, and the activation of an oxidation−reduction cycle between the high and low chemical valences of cerium, leading to improve the electrocatalytic efficiency of NPd. Lastly, the conversion of methanol to formaldehyde, and then to formic acid during electrooxidation is confirmed by using cyclic voltammetry. • Fabrication and characterization of porous CeO 2. • Incorporation of porous CeO 2 as novel support for nanosized palladium. • Study of electrooxidation efficiency of C1 compounds. • Evaluation of the electrooxidation mechanism of C1 compounds. [ABSTRACT FROM AUTHOR]

The growing climate crisis inspires one of the greatest challenges of the 21st century—developing novel power sources. One of the concepts that offer clean, non-fossil electricity production is fuel cells, especially when the role of fuel is played by simple organic molecules, such as low molecular weight alcohols. The greatest drawback of this technology is the lack of electrocatalytic materials that would enhance reaction kinetics and good stability under process conditions. Currently, electrodes for direct alcohol fuel cells (DAFCs) are mainly based on platinum, which not only provides a poor reaction rate but also readily deactivates because of poisoning by reaction products. Because of these disadvantages, many researchers have focused on developing novel electrode materials with electrocatalytic properties towards the oxidation of simple alcohols, such as methanol, ethanol, ethylene glycol or propanol. This paper presents the development of electrode materials and addresses future challenges that still need to be overcome before direct alcohol fuel cells can be commercialized.

A novel 4A zeolite modified platinum/reduced graphene oxide (Pt/RGO-4A zeolite) electrocatalyst has been successfully synthesized by one-step chemical co-reduction method. The electrocatalytic performances of Pt/RGO-4A zeolite electrocatalyst for methanol electrooxidation are investigated in 1.0 M CH3OH containing 1.0 M KOH solution. The results demonstrate that, with loading of 10% of 4A zeolite, Pt/RGO-4A zeolite electrocatalyst shows higher current density of 319.40 mA mg−1 than Pt/RGO electrocatalyst (88.64 mA mg−1) at the potential of 0.70 V. In addition, Pt/RGO-4A zeolite electrocatalyst still exhibits high electrocatalytic activity even after 4000-s operation, suggesting satisfactory long-term durability. The remarkably enhanced electrocatalytic performances are attributed to the nanoporous structure of 4A zeolite, which significantly promotes the dispersion of Pt nanoparticles and provides substantial fast flow paths for reactants. The results suggest a potential application of Pt/RGO-4A zeolite electrocatalyst to methanol electrooxidation. [ABSTRACT FROM AUTHOR]

In this paper, porous NiO with three-dimensional (3D) nanostructures are prepared by a chemical bath deposition (CBD) process in oxalic acid solution at a fixed temperature using Ni foam (NF) as the substrate and Ni source, and followed by an electrochemical activation treatment in an alkaline medium. The special 3D porous structure of the as-prepared NF based NiO (NiO/NF) electrode is benefit for the diffusion of fuels (CH 3 OH/C 2 H 5 OH and urea) during the electrochemical reaction. Besides, the obtained NiO may combine with the remained nickel oxalate (NiC 2 O 4) to further enhance the catalytic performance due to its synergistic effect. At 0.60 V, the electrooxidation current density reached 257 mA cm−2 in 1.0 mol dm−3 NaOH and 0.40 mol dm−3 CH 3 OH, and a high performance of 120 mA cm−2 was achieved in 1.0 mol dm−3 NaOH and 0.10 mol dm−3 C 2 H 5 OH. The oxidation current density reached 222 mA cm−2 in 0.1 mol dm−3 urea with the NaOH concentration of 8.0 mol dm−3 NaOH at around 0.48 V. The facile preparation method, high electrocatalytic activity, low cost and various applications make the NiO/NF be a promising electrode material. • NiO porous nanostructures are prepared by the electrochemical activation of NiC 2 O 4. • NiO/NF owns super electrocatalytic activity towards CH 3 OH/C 2 H 5 OH and urea oxidation. • Remaining NiC 2 O 4 may combine with NiO to form a composite to improve the activity. [ABSTRACT FROM AUTHOR]

In this work, we prepared reduced graphene oxide-supported PtCo nanospheres (PtCo/rGO) by a facile one-step hydrothermal method with the assistance of L-proline as the shape-directing agent. We systematically investigated the effects of various experimental conditions on the morphology and structure of the as-prepared PtCo/rGO hybrids. Compared with commercial Pt/C (10 wt%) and Pt/rGO catalysts, the as-prepared PtCo/rGO has better catalytic activity and poisoning resistance toward methanol electrooxidation and can be used as a promising catalyst for direct methanol fuel cells.Graphical abstract: The rGO-supported PtCo nanosphere hybrids are successfully synthesized by a facile one-pot hydrothermal method with the assistance of L-proline. L-proline acts as shape-controlled agent for synthesizing PtCo/rGO. The as-prepared PtCo/rGO hybrids exhibit a higher electrocatalytic activity and poisoning-resistant ability for methanol oxidation in acidic media. [ABSTRACT FROM AUTHOR]

Abstract A new method for the synthesis of n Ru⋅ m Pt⋅(H x −3 n −2 m MoO 3) composite based on the redox reaction between the reduced forms of molybdenum bronzes and the solution containing platinum and ruthenium species is proposed. The uniform distribution of Pt and Ru over the electrode surface was observed in the case of their codeposition from the solution containing both platinum and ruthenium compounds. The obtained composite contained platinum mainly in the metallic state, while ruthenium was found in both metallic and oxidized states. The manufactured electrodes were characterized by high catalytic activity in the reactions of carbon monoxide and methanol oxidation. The rate of the methanol oxidation reaction (MOR) on n Ru⋅ m Pt⋅(H x −3 n −2 m MoO 3) was 4–5 times higher in comparison with that on n Pt⋅(H x −2 n MoO 3) and ∼30 times higher as compared with that on Pt ed /GC. On the basis of the obtained data, one can state the additive effect of ruthenium and molybdenum species on methanol electrooxidation. Graphical abstract Image 104 [ABSTRACT FROM AUTHOR]

Abstract A novel electrocatalytic system was developed to realize one-pot conversion of organic pollutants into liquid fuels such as methanol (CH 3 OH) and ethanol (C 2 H 5 OH). The process combines the catalytic oxidation of organic pollutants with electrocatalytic reduction of CO 2. We first coupled the electrocatalytic process with SO 4 •−-based advanced oxidation processes (AOPs) for the degradation of 4-nitrophenol (4-NP) using a 3D-hexagonal Co 3 O 4 anode. In this step, 4-NP was mineralized to CO 2 , and then the CO 2 was converted to CH 3 OH and C 2 H 5 OH by electrocatalytic reduction using a flower-like CuO cathode. The experimental results show the destruction of 4-NP (60 mL, 10 mg/L) can be as high as 99%. In addition, the yields of CH 3 OH and C 2 H 5 OH were 98.29 μmol/L and 40.95 μmol/L, respectively, which represents a conversion of 41.8% of 4-NP into liquid fuels; the electron efficiency was 73.1%. In addition, we found that 3D-hexagonal arrays of Co 3 O 4 with different morphologies can be obtained by adding different amounts of urea. We also investigated the formation mechanism of novel 3D-hexagonal Co 3 O 4 arrays for the first time. A mechanism was proposed to explain the electrocatalytic steps involved in the conversion of 4-NP to CH 3 OH and C 2 H 5 OH and the synergetic effects between AOPs and electrocatalysis. Graphical abstract Image 1 Highlights • Organic pollutants to hydrocarbons was fulfilled in one electrocatalytic system. • SO 4.•− for high-efficient degradation of organic pollutants was proposed. • 3D-hexagonal Co 3 O 4 array was prepared and formation mechanism was proposed. • A mechanism was proposed to explain the electrocatalytic steps. [ABSTRACT FROM AUTHOR]

In this study, carbon nanotube supported Pd, PdAu, and PdAuCo electrocatalysts (Pd/CNT, PdAu/CNT, and PdAuCo/CNT) were synthesized via NaBH4 reduction method at varying molar atomic ratios to investigate their performance for methanol and ethylene glycol electrooxidation in alkaline media. The characterization of the as-prepared catalysts was performed using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, N2 adsorption-desorption, and small-angle X-ray-scattering analysis. From the physical characterization results, it was seen that PdAuCo/CNT catalysts were successfully prepared. X-ray photoelectron spectroscopy results showed that Pd and Au atoms employed in the preparation of the catalysts exist mainly in their elemental state. X-ray diffraction results indicated the formation of a new phase. Furthermore, the mean particle size of Pd50Au30Co20/CNT was determined as 7.9 and 8.7 nm using small-angle X-ray scattering and transmission electron microscopy analyses. Pd50Au30Co20/CNT demonstrated the type V adsorption isotherms with H1-type hysteresis, which indicates the mesoporous structure of the catalyst. Electrocatalytic activity of the catalysts for ethylene glycol and methanol electrooxidation was investigated with cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic activity of Pd50Au30Co20/CNT was determined as 262 and 694 mA/mg Pd for methanol and ethylene glycol electrooxidation. In accordance with cyclic voltammetry and electrochemical impedance spectroscopy results, Pd50Au30Co20/CNT possesses the highest electrocatalytic activity for both electrooxidation. [ABSTRACT FROM AUTHOR]

The reactions of electrooxidation of methanol and formic acid pertain to the most important model electrocatalytic processes and are used in direct low-temperature fuel cells. The electrooxidation mechanisms of these substances were actively studied for many decades. Considerable progress in this field was achieved due to the combined use of electrochemical techniques, in situ IR spectroscopy, differential electrochemical mass spectrometry, isotope-kinetic method, ab initio calculations in terms of the density functional theory, and comparison with the results of gas-phase investigations. The fundamental role in understanding the mechanism of processes was played by measurements on single-crystal faces and surfaces with the known ratio of terraces, steps, and kinks. This allowed the information accumulated for catalysts formed by metal nanoparticles to be interpreted and the role of the structure and size factors in electrocatalysis to be revealed. Attention is focused on the nature of adsorbates and intermediates, the detailed reaction routes, the mechanism of possible slow stages, the pH effects, the roles of the nature of anions in acidic solutions and of the nature cations in alkaline solutions. The effect of the catalyst loading and the multistage character of electrooxidation processes on the efficiency of real fuel cells is noted. The mechanisms of Langmuir–Hinshelwood and Eley–Rideal are analyzed as applied to electrooxidation processes as well as certain peculiarities of CO adsorbate electrooxidation. The results on the mechanism of interaction between adsorbed oxygen and С1-compounds are discussed. The specific features of processes on bimetallic surfaces and the strategy for designing catalysts based on the views on the mechanism of processes, the control over the structure/ composition of the surface and its specific decoration with metal adatoms are considered. Certain topical research directions are formulated aimed at deeper understanding of the mechanisms of electrooxidation of C1-compounds. [ABSTRACT FROM AUTHOR]

Abstract: Activities of the synthesized trimetallic catalysts PtRuPd/C and PtRuIr/C supported on highly dispersed carbon soot from solutions of coordination compounds of the corresponding metals are studied in the electrooxidation of methanol. According to the data of voltammetry, the Pt0.43Ru0.47Pd0.1/C and Pt0.44Ru0.46Ir0.1/C catalysts are not inferior to the commercial catalyst Pt0.5Ru0.5/C in specific characteristics, which is consistent with the data of structural studies and the electrochemical and power characteristics of the membrane electrode unit tested in the composition of a single methanol/air fuel cell. [ABSTRACT FROM AUTHOR]

Abstract: The interaction between precious metal nanoparticles and the support plays an important role in improving poisoning tolerance of Pt‐based catalysts and thus maintaining their activity and stability. Here, a dendrite‐like Mn3O4 was fabricated and used as a support for Pt nanoparticles towards the methanol electrooxidation reaction. The nanoparticles were deposited chemically on surfaces of the dendritic Mn3O4, which was prepared through calcination of MnO2 hollow microspheres. The Mn3O4 support not only provided an appropriate base for the formation of nanosized and homogeneous platinum particles (about 2.6 nm in size), but also increased Pt0 binding energy owing to a strong electronic interaction. By combining the advantages of the small‐size, fine dispersion and enhanced binding energy of Pt nanoparticles, the Pt/Mn3O4 composite exhibited enhanced catalytic activity, poisoning tolerance and stability for methanol electrooxidation. [ABSTRACT FROM AUTHOR]

The preparation of nanomaterials with superior catalytic properties through simple and rapid protocols is a task of great importance. In the present study, we demonstrate the direct synthesis of trimetallic PdRuPt nanowire networks through the reduction of the corresponding metal precursors with NaBH4, in the presence of KBr and polyvinylpyrrolidone (PVP). The elemental composition of the final products could be easily tuned by varying the added amounts of metal precursors. The obtained nanomaterials were then used as catalysts for methanol electrooxidation in an acidic medium. Among the synthesized PdRuPt and PtPd nanowire networks, Pd0.97Ru0.44Pt exhibits the highest catalytic activity and durability, along with a specific activity 3.5 times higher than that of commercial Pt/C. The enhanced catalytic properties of the present nanowiresystems are attributed to their unique structures and the introduction of Ru into PtPd nanocrystals with outstanding properties. [ABSTRACT FROM AUTHOR]

Ni–metal oxide (Fe 2 O 3 , ZnO, Co 3 O 4 and MnO 2 ) nanocomposites were synthesized on carbon substrates by electrodeposition technique. These catalysts were tested as anodes for electrooxidation of both methanol and ethanol. To study the chemical composition of the deposits, energy dispersive X-ray spectroscopy (EDX) was used and the maximum wt% of metal oxides in the prepared composites was found to be 11.4, 11.7, 9.3 and 3.8 for Fe 2 O 3 , ZnO, MnO 2 and Co 3 O 4 , respectively. The morphology of the catalysts surface is significantly affected by the existence of metal oxides as confirmed by scanning electron microscope (SEM) images. The phase structure and the particle size of the catalysts were recognized from X-ray diffraction (XRD). A reduction in the Ni grains was seen in the matrix of the composites compared with that of Ni/C. Cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) were employed to study the electrocatalytic activity of the prepared nanocomposites. All the results displayed a satisfactory electrocatalytic activity, better stability, lower charge transfer resistance, and stronger resistance to the poisoning of the nanocomposites compared with that of Ni/C. A synergistic effect among multiple active sites due to the presence of mixed oxides for the nanocomposites could enhance their electrocatalytic activity. The performance of the different prepared catalysts towards the electrooxidation process was established in the order of: Ni–Fe 2 O 3 /C > Ni–ZnO/C > Ni–Co 3 O 4 /C > Ni–MnO 2 /C > Ni/C. Ni–metal oxide nanocomposites appeared to be promising and less expensive anode catalysts for fuel cell applications. [ABSTRACT FROM AUTHOR]

In order to emphasize the importance of electrolyte-tuning in the nitroxyl radicals mediated electrocatalytic reactions, methanol and glycine electrooxidation reactions catalyzed by TEMPO under different properties (pH, identity, concentration) of buffer solutions were investigated by cyclic voltammetry. It was discovered that in both carbonate buffer solutions and borate buffer solutions, catalytic abilities increase with the rising of pH for both glycine electrooxidation and methanol electrooxidation. The electrocatalytic performance is also affected by the identity of buffer, for both cases of glycine and methanol, the electrooxidation activities in borate buffer solutions are apparently higher than those in carbonate buffer solutions. For both glycine and methanol electrooxidation, relationships between concentrations of carbonate ions and relative catalytic current densities were observed to be volcano-shaped, while electrocatalytic abilities increase with the increasing of concentrations of borate ions within the studied concentration range. These findings suggest that the electrolyte should be treated as important as the catalyst in the designing of nitroxyl radicals mediated electrocatalytic systems. [ABSTRACT FROM AUTHOR]

In this work, first poly (pyrrole- co -aniline) (PPCA) hollow nanosphere (HN) as a catalyst support material is fabricated through in-situ emulsion polymerization. Then we reported a one-step and template-free approach to fabricate Pd NFs on a PPCA HN coated glassy carbon electrode by a facile electrochemical approach. Several techniques such as FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy) and EDS (energy dispersive spectroscopy) were utilized for the characterization of the synthesized materials. The catalytic performance of Pd NFs/PPCA HN catalyst is evaluated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy toward methanol oxidation as a model reaction in alkaline media. The comparison of specific activities for Pd NFs/PPCA HN (1.79 mA cm −2 ), Pd NFs/PPy (1.28 mA cm −2 ), Pd NFs/PANI (0.93 mA cm −2 ) and Pd NFs (0.78 mA cm −2 ) shows that the PPCA supported Pd NFs with high surface area exhibits the excellent electrocatalytic activity than other electrodes for the electro-oxidation reaction in alkaline media. This might be due to the easier charge transfer at conductive copolymer interfaces, higher electrochemically accessible surface areas and electronic conductivity. This strategy provides a promising platform for direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

In this study, Ni-Al layered double hydroxide (LDH)-Pt nanoparticles (PtNPs) as an inorganic nanocomposite was electrosynthesized on the glassy carbon electrode (GCE) by a facile and fast two-step electrochemical process. Structure and physicochemical properties of PtNPs/Ni-Al LDH/GCE were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry and electrochemical methods. Then, electrocatalytic and stability characterizations of the PtNPs/Ni-Al LDH/GCE for methanol oxidation in alkaline media were investigated in detail by cyclic voltammetry, chronoamperometry, and chronopotentiometry measurements. PtNPs/Ni-Al LDH/GCE exhibited higher electrocatalytic activity than PtNPs/GCE and Ni-Al LDH/GCE. Also, the resulted chronoamperograms indicated that the PtNPs/Ni-Al LDH/GCE has a better stability. [ABSTRACT FROM AUTHOR]

In the present research, the electro oxidation of methanol was investigated by different electrochemical methods at a carbon paste electrode (CPE) modified with bis(salicylaldehyde)-nickel(II)-dihydrate complex (Ni(II)-BS) and reduced graphene oxide (RGO) (which named Ni(II)-BS/RGO/CPE) in an alkaline solution. This modified electrode showed very efficient activity for oxidation of methanol. It was found that methanol was oxidized by NiOOH groups generated by further electrochemical oxidation of nickel (II) hydroxide on the surface of the modified electrode. The rate constant and electron transfer coefficient were calculated to be 2.18 s-1 and 0.4, respectively. The anodic peak currents revealed a linear dependency with the square root of scan rate. This behaviour is the characteristic of a diffusion controlled process, so the diffusion coefficient of methanol was found to be 1.16×10-5 cm2 s-1 and the number of transferred electron was calculated to be 1. Moreover, differential pulse voltammetry (DPV) investigations showed that the peak current values were proportional to the concentration of methanol in two linear ranges. The obtained linear ranges were from 0.5 to 100.0 mM (R2=0.991) and 400.0 to 1300.0 mM (R2=0.992), and the detection limit was found to be 0.19 mM for methanol determination. Generally, the Ni(II)-BS/RGO/CPE sensor was used for determination of methanol in an industrial ethanol solution containing 4.0% methanol. [ABSTRACT FROM AUTHOR]

In this paper, polypyrrole@multi-walled carbon nanotubes (PPy@MWCNTs) nanocomposite as a catalyst support material is fabricated. Pd nanoflowers (NFs) were deposited on a PPy@MWCNTs modified glassy carbon electrode (GCE) by a facile electrochemical approach. The morphology and composition of the Pd NFs/PPy@MWCNTs are characterized by SEM (scanning electron microscopy) and EDS (energy dispersive spectroscopy), respectively. The catalytic performance of Pd NFs/PPY@MWCNTs catalyst is examined by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy toward methanol oxidation reaction (MOR) in alkaline media. The mass activity of Pd NFs/PPY@MWCNTs (725 mA mg −1 ) is 8.09 times higher than that of the Pd NFs catalyst (89.6 mA mg −1 ). Meanwhile, the ratio of forward current (j f ) to reverse current (j b ) for the polymer supported catalyst is almost 2.6 times higher than that of the Pd NFs. Furthermore, PPY@MWCNTs produces a high activity to electrocatalyst, which might be due to higher electrochemically surface area and electronic conductivity. This strategy provides a promising platform for direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Hierarchical nanostructures are very universal in the natural world. However, to date most of synthetic approaches are just capable of producing simple nanomaterials, such as nanospheres, nanorods, nanowires, nanopolyhedrons, etc. Fabrication of complex nanostructures has to depend on the assembly of single nano-building blocks and e-beam lithography. Thus, it is imperative to create complex nanostructures by direct synthetic methods. Herein, three-dimensional fern-like Au nanostructures (3DFGNs) were achieved simply by one-step glycine-assisted electrodeposition. The effects of glycine concentration, electrode substrate and deposition potential on the growth of Au nanostructures were explored. Over the range of glycine concentration from 1.0 mmol/L to 10 mmol/L, all Au nanostructures are 3DFGNs except for the difference of the average diameter of branches. The oriented growth of 3DFGN is attributed to the specific adsorption of NH 2 groups of glycine. Each fern-like dendrite of 3DFGN is a four-fold symmetric single-crystal growing along the (111) direction. As-prepared 3DFGNs show morphology- and size-dependent electrocatalytic performance towards methanol oxidation. Optimized 3DFGN exhibits satisfactory electrocatalytic activity and long-term durability, ∼3 times in the specific activity better than island-like Au aggregates electrodeposited without glycine. [ABSTRACT FROM AUTHOR]

Carbon-supported platinum nanoparticles are successfully synthesized and characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). Electrocatalytic activity and stability of the Pt/C catalyst for 1,2-propanediol, 2-propanol and methanol electrooxidation was investigated using cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). According to the obtained results, the activity of the Pt/C catalyst for 1,2-propanediol oxidation reaction was higher than that of the other alcohols. Multi-scan cyclic voltammetry after 100 CV cycles revealed that the Pt/C catalyst has great catalytic activity, high poison-tolerance ability and improved electrochemical stability for 1,2-propanediol oxidation compared with methanol and 2-propanol. This indicates a lower poisoning effect of the adsorbed intermediates on the Pt/C performance in 1,2-propanediol oxidation. Infrared spectroscopy measurements after 100 CV cycles in methanol oxidation indicated that adsorbed CO specie is detected on the surface of Pt/C catalyst, but not in 1,2-propanediol oxidation. Comparison of the corresponding EIS measurements after 1st and 100th cycles showed that 1,2-propanediol has the best performance in terms of charge transfer resistance and specific capacitance. [ABSTRACT FROM AUTHOR]

This present study reports the development of novel catalyst support of amine terminated cyclophosphazene/cyclophosphazene/hexafluoroisopropylidenedianiline-carbon nanotube (ATCP/CP/HFPA-CNT) composite. The ATCP/CP/HFPA-CNT composite has been used as a catalyst support for platinum (Pt) and platinum-gold (Pt-Au) nanoparticles towards electrooxidation of methanol in alkaline medium. The obtained anode materials were characterized by X-ray diffraction, transmission electron microscope and energy dispersive X-ray analysis. Electrocatalytic performances of Pt/ATCP/CP/HFPA-CNT and Pt-Au/ATCP/CP/HFPA-CNT catalysts were investigated by cyclic voltammetry, CO stripping and chronoamperometric techniques. The electrooxidation of methanol and CO stripping results conclude that the metal nanocatalyst embedded with ATCP/CP/HFPA-CNT composite shows significantly higher anodic oxidation current, more CO tolerance and lower onset potential when compared to that of the Pt/CNT and Pt/C (Vulcan carbon) catalysts. [ABSTRACT FROM AUTHOR]

nPd · (HMoO)/GC electrodes (0 < n < 1) were obtained by currentless redox reaction between hydrogen-containing molybdenum bronzes and palladium(II) chloride. The composites were characterized by electrochemical methods and by SEM, TEM, XRD, XPS, and AES-ICP. The morphology, structure, and composition of the electrodes depend on the degree of reduction of the starting molybdenum bronze. The use of red molybdenum bronze HMoO ( x ≈ 1.55) led to the formation of a composite characterized by longer palladium/molybdenum oxide compound boundaries than in the case of green molybdenum bronze ( x ≈ 1.9). On the nPd · (HMoO)red/GC electrodes, the catalytic effect with respect to methanol electrooxidation (MEO) was significant, while formic acid electrooxidation (FAEO) was accelerated insignificantly. Possible reasons for the difference in the effect of Pd modification with molybdenum bronzes on MEO and FAEO were discussed. [ABSTRACT FROM AUTHOR]

The present work is focused on the synthesis of platinum (Pt)and platinum-tin (Pt-Sn) nanoparticles decorated poly(aniline)-rice husk ash (PANI-RHA) composite by the chemical reduction of their respective metal salts. The obtained Pt/PANI-RHA and Pt-Sn/PANI-RHA composites were characterized by FT-IR, XRD, SEM, EDAX and HR-TEM analysis. Platinum nanoparticles were also decorated on RHA and PANI for comparative studies. The synthesized electrocatalysts have been subjected to electrooxidation of methanol by cyclic voltammetry. It has been concluded that the Pt nanoparticles decorated PANI-RHA composite exhibits a remarkable enhancement for the electrochemical oxidation of methanol when compared with Pt/PANI and Pt/RHA composites. So, PANI-RHA composite has proven to be a good supporting material for alcohol fuel cell applications. Further, Pt-Sn bimetallic nanoparticles decorated PANI-RHA composite exhibit a remarkable enhancement for the electrochemical oxidation of methanol compared to that of Pt/PANI-RHA catalyst. Hence, the above results suggest that Pt-Sn/PANI-RHA composite is a potent and low cost electrocatalyst for fuel cell industries. [ABSTRACT FROM AUTHOR]

Uniform CeO 2 nanorods (CeO 2 -r) and CeO 2 nanoparticles (CeO 2 -p) are synthesized by hydrothermal method and are used as supports to load Pt nanoparticles (indexed as Pt/CeO 2 -r & Pt/CeO 2 -p) for methanol electrooxidation. HRTEM images indicate that the synthesized CeO 2 -r are covered by (1 0 0) and (1 1 0) facets which own higher surface energy compared to CeO 2 -p with (1 1 1) facets. Electrochemical characterizations demonstrate Pt/CeO 2 -r shows excellent specific activity which is 1.6 and 10 times higher than Pt/CeO 2 -p and commercial Pt/C (indexed as Pt/C-JM) towards electrooxidation of methanol. By in-situ FTIR spectroscopic investigation, much higher CO 2 productivity is observed at low potential on Pt/CeO 2 -r that implies strong anti-poisoning ability during methanol electrooxidation. The significant improved electrocatalytical performance is attributed to the existence of CeO 2 nanorods with high energy surfaces. [ABSTRACT FROM AUTHOR]

This study offers a unique insight into the use of high surface area metallic tin as support material for platinum catalysts for fuel cell application. We have synthesized high surface area metallic β-tin nanostructures (TNSs) in aqueous solutions by novel one-pot process and used it as a platinum catalyst support in methanol electrooxidation reaction. Rigorous study of parameters controlling the size and shape of TNSs was performed, including selected surfactant molecules at various concentrations, tin salts, and the addition of sodium citrate. Rod-shaped particles with a 50-nm diameter and 500-nm length were obtained from solutions of selected surfactant in concentrations of 1-20 mM by sodium borohydride reduction. These particles had a β-Sn crystalline core with a main lattice plane of (101) and were covered by a 4-nm oxide shell. A maximal surface area of 170 m g was measured from a sample prepared by using low concentration of sodium dodecyl sulfate (SDS) (1 mM). This sample is composed of nanorods and nano semi-spherical shape tin particles. Addition of sodium citrate, which acts as a Sn ion ligand, yields longer rods. Electrochemical oxidation of methanol on platinum catalyst, supported on metallic Sn nanostructure, exhibits a high activity, which is comparable to commercial carbon-supported platinum catalysts. In situ surface-enhanced Raman (SER), emphasizing the role of surface oxides on the methanol oxidation activity, further studied methanol oxidation on Pt/TNS, Pt/C, and Pt-Sn alloy catalyst. [ABSTRACT FROM AUTHOR]

Different Ni−MnO x /C electrocatalysts were prepared by chemical reduction of nickel ions at MnO x /C, containing various metal oxide weight percentages, as a support. Sodium borohydride was employed as a reducing agent with the aid of microwave irradiation. Electrocatalyst surface morphology, crystalline structure and chemical composition were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX), respectively. Incorporating manganese oxide in Ni−MnO x /C resulted in the formation of smaller and homogeneously distributed nickel nanoparticles. Electrocatalytic activity of Ni−MnO x /C towards methanol oxidation reaction in KOH solution was investigated using cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The oxidation current density was enhanced with increasing MnO x weight percentage to achieve the highest activity at Ni−MnO x /C containing 7.5 wt.% MnO x . The electrocatalyst stability during long-time operation was examined. A lower charge transfer resistance value was measured at Ni−MnO x /C surface when methanol was introduced to the supporting electrolyte. A faster electron transfer rate was observed when MnO x was added in an increased content. [ABSTRACT FROM AUTHOR]

Based on the ultrasonic cavitation assisted hydrogen implosion method, Pt nanoparticles (NPs)/nitrogen-doped graphene nanohybrid scrolls (Pt NPs/N-GNSs) were synthesized. As the results of the N-doping and high reduction degree of graphene, and scroll structure of the nanohybrids, the Pt NPs/N-GNSs electrocatalyst shows excellent performance in the direct oxidation of methanol: low onset and peak potentials, high oxidation current, and good long-term cycle stability. The Pt NPs/N-GNSs should have great promising applications in heterogeneous catalysis and fuel cells. [ABSTRACT FROM AUTHOR]

Carbon ceramic electrode (CCE), a new electrode substrate, was prepared by sol-gel procedure and used for the electropolymerization of aniline and dispersion of platinum nanoparticles into the resulting polyaniline (PANI) film. The microscopic structure and morphology of the CCE, CCE/PANI and CCE/PANI/Pt are characterized by scanning electron microscopy. The electrochemical and catalytic activities of the CCE/PANI/Pt were studied in 0.3 M HSO solution. The electrocatalytic oxidation of methanol at the CCE/PANI/Pt has been investigated using cyclic voltammetric and chronoamperometric methods. The catalytic activity of Pt-coated PANI film on the CCE surface was compared with glassy carbon and Pt polyaniline/platinum-modified electrodes. [ABSTRACT FROM AUTHOR]

Electrooxidation of 2,4,6-tribromophenol on platinum gauze electrode in 90 % (v/v) alcohol (methanol, ethanol, propan-1-ol, butan-1-ol) was studied. Products were investigated by gas chromatography/mass spectrometry. Structures of several different types of monomeric as well as dimeric alkoxy derivatives have been suggested according to mass spectra of the detected products. Series of 2,6-dibromo-4-alkoxyphenols, 2,4,6-tribromo-6-alkoxycyclohexa-2,4-dien-1-ones and 2,6-dibromo-6-alkoxycyclohex-2-ene-1,4-diones were found. By analogy to identified monomeric alkoxy derivatives, a serie of dimeric 2,6-dibromo-4-(2,6-dibromo-4-alkoxyphenoxy)phenols was suggested and identified in respective chromatograms as well. [ABSTRACT FROM AUTHOR]

We report a graphene three-dimensional network (G3DN) structure on a Si substrate, which is used as Pt nanoparticle support for effective electrocatalytic oxidation of methanol and ethanol. The controllable Pt loading on the G3DN is conducted by a facile, repeatable and environmentally friendly approach. The influence of graphene architecture on electrocatalytic activities is comparatively investigated by loading the same amount of Pt on the G3DN and on commercial graphene sheets (CGS). The Pt/G3DN (0.01 mg Pt cm −2 ) electrode exhibits a tremendous electrocatalytic activity for the oxidation of methanol and ethanol with oxidation current of 910.11 mA mg Pt −1 and 246.69 mA mg Pt −1 respectively owing to its high density of three-dimensional active sites, wavy sheet-network channels and synergistic effect of Pt and graphene. The peak current density ratio of the forward to backward potential scan is 2.79 and 0.65 for the methanol and ethanol oxidation respectively. The results reveal excellent characteristics of the Pt/G3DN electrode, such as easy preparation, high catalytic activity, stability and tolerance toward poisoning effects for the electrooxidation of methanol. [ABSTRACT FROM AUTHOR]

Phenylphosphonic acid (PPA)-assisted one-pot method for preparation of PtRu nanoparticles with high dispersion and stabilization on carbon nanotubes (CNTs) is reported. Based on the π-π stacking between phenylphosphonic acid and CNTs, abundant phosphonate groups were uniformly introduced on CNTs' surface, which significantly not only improve the solubility and dispersibility of CNTs in polar solvents but also enhance the dispersion of PtRu nanoparticles on CNTs' surface. The obtained PtRu/PPA-CNT electrocatalysts are characterized by transmission electron microscopy, infrared spectroscopy, thermal gravimetric analysis, X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray powder diffraction. The results reveal that CNTs were successfully functionalized by PPA, and PtRu nanoparticles were uniformly dispersed on PPA-CNT surface with average particle diameter of 2.5 nm. Electrochemical studies certified that PtRu/PPA-CNT electrocatalysts have much higher electrocatalytic activity and stability for methanol oxidation in comparison with PtRu nanoparticles supported on the pristine CNTs because of their highly electrochemical surface area at 612.7 cm mg. [ABSTRACT FROM AUTHOR]

Abstract: A new method for the synthesis of the catalyst systems Pt–Mo was suggested. nPt0(H x−2n MoO3)/GC electrodes were prepared by a redox reaction between the hydrogen-containing molybdenum bronzes and potassium tetrachloroplatinate (II) in acid solutions at open circuit potential. The electrodes were characterized by CVA, SEM, X-ray microanalysis, XRD, XPS and ICP-AES. Pt0conglomerates formation with nonuniform distribution over the molybdenum bronzes surface has been revealed. nPt0(H x−2n MoO3)/GC electrodes showed high catalytic activity (not inferior to Pt–Ru-catalyst) in the oxidation of carbon monoxide and methanol as compared with Pt/GC-electrodes. Catalytic effect is apparently achieved by effective oxidation of strongly chemisorbed species (COads, HCOads), which occurs at boundaries platinum – molybdenum oxide. Therefore nPt0(H x−2n MoO3) can be considered as one of perspective catalysts for DMFC. [Copyright &y& Elsevier]

Electrocatalytic oxidation of methanol and some other primary alcohols on a glassy carbon electrode modified with multi-walled carbon nanotubes and nano-sized nickel oxide (GCE/MWNT/NiO) was investigated by cyclic voltammetry and chronoamperometry in alkaline medium. The results were compared with those obtained on a nickel oxide-modified glassy carbon electrode (GCE/NiO). Both the electrodes were conditioned by potential cycling in the range of 0.1-0.6 V versus Ag/AgCl in a 0.10 M NaOH solution. The effects of various parameters such as scan rate, alcohol concentration, thickness of NiO film, and real surface area of the modified electrodes were also investigated and compared. It was found that the GCE/MWNT/NiO-modified electrode possesses an improved electrochemical behavior over the GC/NiO-modified electrode for methanol oxidation. [ABSTRACT FROM AUTHOR]