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Glycerol electro‐oxidation reaction was performed in an alkaline environment with an anion exchange membrane fuel cell (AEMFC) operating in bath mode at low Pt‐loadings. BAE‐synthesized Pt/C and PtCe/C nanostructured catalysts were used as anode materials during 4‐hour operation to selectively obtain 65 % and 41 % of glycerate as main product, respectively. The modification of Pt with Ce improved the catalytic activity of the Pt/C catalyst generating 30 % more energy density after 4‐hour operation by achieving a higher degree of glycerol oxidation in cogeneration with added‐value products confirmed by spectroelectrochemical (in situ FTIR) and liquid chromatography coupled with mass spectrometry (LC–MS) analyses. The bifunctional mechanism generated by the presence of Ce is used to explain the improvement in the catalytic activity of Pt/C, due to the properties of this rare earth element to adsorb oxygenated species (OH−) and promote oxidation. The cathode material was a polyol‐synthesized PdFe/C electro‐catalyst for ORR that presented impressive stability and tolerance to glycerol. [ABSTRACT FROM AUTHOR]

Experimental evidence for Pd-based structure modification of electrocatalysts with hydrogen during their chemical synthesis is still missing. Therefore, in situ X-ray diffraction (XRD) techniques were as used to investigate hydrogen insertion into the lattice of Pd nanomaterials during their preparation. It was shown that the use of NaBH4 as reducing agent led to PdH x whereas L-ascorbic acid gave Pd nanoparticles. The subsequent influence of hydrogen insertion on the catalytic properties of Pd nanostructures was demonstrated by using carbon monoxide and glucose as probing molecules. High active surface areas and catalytic activities were found for the unmodified Pd nanostructures through electrochemical studies. Notably, the reducing agent has a significant effect on the size distribution of the nanoparticles. Its use can precisely and effectively tune their catalytic properties. Consequently, the remarkable behavior uncovered herein provides new strategic routes that can be used for the preparation of Pd-based nanomaterials. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) is the oldest studied and most challenging of the electrochemical reactions. Due to its sluggish kinetics, ORR became the major contemporary technological hurdle for electrochemists, as it hampers the commercialization of fuel cell (FC) technologies. Downsizing the metal particles to nanoscale introduces unexpected fundamental modifications compared to the corresponding bulk state. To address these fundamental issues, various synthetic routes have been developed in order to provide more versatile carbon-supported low platinum catalysts. Consequently, the approach of using nanocatalysts may overcome the drawbacks encountered in massive materials for energy conversion. This review paper aims at summarizing the recent important advances in carbon-supported metal nanoparticles preparation from colloidal methods (microemulsion, polyol, impregnation, Bromide Anion Exchange...) as cathode material in low temperature FCs. Special attention is devoted to the correlation of the structure of the nanoparticles and their catalytic properties. The influence of the synthesis method on the electrochemical properties of the resulting catalysts is also discussed. Emphasis on analyzing data from theoretical models to address the intrinsic and specific electrocatalytic properties, depending on the synthetic method, is incorporated throughout. The synthesis process-nanomaterials structure-catalytic activity relationships highlighted herein, provide ample new rational, convenient and straightforward strategies and guidelines toward more effective nanomaterials design for energy conversion. [ABSTRACT FROM AUTHOR]

An 'abiotic' biofuel cell composed of catalytic electrodes modified with inorganic nanoparticles (NPs) deposited on carbon black (CB) was used to activate a wireless information transmission system. The cathode and anode were made of carbon paper modified with Pt-NPs/CB and buckypaper modified with Au80Pt20-NPs/CB, respectively. The cathode/anode pair was implanted in orange pulp extracting power from its content (glucose and fructose in the juice). The open circuit voltage, Voc, short circuit current density, jsc, and maximum power produced by the biofuel cell, Pmax, were found as 0.36 V, 1.3 mA cm−2 and 182 µW, respectively. The voltage produced by the biofuel cell was amplified with an energy harvesting circuit and applied to a wireless transmitter. The present study continues the research line where different implantable biofuel cells are used for activation of electronic devices. [ABSTRACT FROM AUTHOR]

An 'abiotic' biofuel cell composed of catalytic electrodes modified with inorganic nanostructured species was used to activate a pacemaker. The catalytic nanoparticles of various compositions, Au xPt y, deposited on carbon black (CB) were prepared and extensively characterized to select the species with selectivity for glucose oxidation and oxygen reduction. Then two kinds of 3D-electrode materials with different morphology, buckypaper composed of carbon nanotubes (ca. 50 nm diameter) and carbon paper made of carbon fibers (ca. 7 µm diameter), were used in a combination with different catalytic species. Finally, Au/CB nanospecies deposited on buckypaper were selected for catalyzing glucose oxidation (composing the biofuel cell anode) and Au60Pt40/CB species deposited on carbon paper were selected for catalyzing oxygen reduction (composing the biofuel cell cathode). The catalytic electrodes were characterized by cyclic voltammetry in an aqueous buffer solution and the polarization function for the biofuel cell was studied in a human serum solution. The open circuit voltage, Voc, short circuit current density, jsc, and maximum power produced by the biofuel cell, Pma x, were found as 0.35 V, 0.65 mA cm−2 and 104 µW, respectively (in human serum at 5.4 mM glucose). The biofuel cell produced the steady state open circuit voltage over 10 hours with its slow decrease over 50 hours originating from the glucose depletion and slow mass-transport within the 3D-electrode. The voltage produced by the biofuel cell was amplified with an energy harvesting circuit and applied to a pacemaker resulting in its proper operation. The present study continues the research line where different implantable (enzyme-based or abiotic) biofuel cells are used for the activation of biomedical electronic devices, e.g., pacemakers. [ABSTRACT FROM AUTHOR]

Abstract: RuO2 nanoparticles are synthesized by Instant method using Li2CO3 as stabilizing agent, under microwave irradiation at 60°C and investigated for the anodic oxygen evolution reaction (OER) and for their supercapacitance properties in 0.5M H2SO4 medium. Structural and morphological characterizations of RuO2 are investigated by in situ X-ray diffraction (XRD), thermogravimetric analysis (TG-DTA), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDS) and Raman spectroscopy. The TEM images of as prepared material show the uniform distribution of RuO2 nanoparticles with mean diameter of ca. 1.5nm. Analysis on as prepared material indicates the structural formula as [RuO2·2.6H2O] 0.7H2O with low crystallinity. The influence of annealing temperature on RuO2 is studied in light of electrocatalytic activity for oxygen evolution reaction (OER) and capacitance. Electrochemical performances of RuO2 electrodes are followed by current–potential curves, galvanostatic charge–discharge cycles and evolved oxygen measurements. The amount of oxygen gas evolved during the OER by the crystalline RuO2 is found to be consistent with the electrical energy supplied to the catalyst. The cyclic voltammogram of RuO2 exhibits the typical capacitance behavior with highly reversible nature. The specific capacitance of hydrous RuO2 is found to be 737Fg−1 at the scan rate of 2mVs−1, by the balanced transport of proton through the structural water and electron transport along dioxo bridges, which makes a suitable material for energy storage. The specific capacitance decreases with increase in the crystallinity of RuO2. The present study shows the potential method to synthesize rapid and uniform nano particles of RuO2 for water electrolysis and supercapacitors. [Copyright &y& Elsevier]

This review presents in a comprehensive ways the chemical methods used to functionalize gold nanoparticles with focus on anti-cancer applications. The review covers the parameters required for the synthesis gold nanoparticles with defined shapes and sizes, method for targeted delivery in tumours, and selected examples of anti-cancers compounds delivered with gold nanoparticles. A short survey of bioassays for oncology based on gold nanoparticles is also presented. [ABSTRACT FROM AUTHOR]

Review: [73 refs. [ABSTRACT FROM AUTHOR]