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Until now, the fabrication of electrocatalysts to guarantee long life of fuel cells and low consumption of noble metals remains a major challenge. The electrocatalysts based on metals or metal oxides which are used today are limited by the complexity of their synthesis processes and require several steps before depositing the catalysts on the substrate. Herein is described a chemical synthesis process that consists of a single-step synthesis and direct deposition of catalysts nanoparticles such as gold (Au), palladium (Pd) and platinum (Pt) in the thickness of a carbon-fibers-based porous transport layer (PTL). The synthesis process essentially consists of dissolving in the same PGMEA (Propylene glycol methyl ether acetate) solvent a metal precursor (HAuCl4 or PdNO2 or PtCl4) and a homopolymer PMMA (Polymethylmetacrylate), then the metal solution is deposited on the surface of the PTL after cleaning. Special emphasis is made on Pt-based materials. The obtained PTL-supported nanoparticles were firstly characterized by scanning electron microscopy (SEM) to evaluate their morphology, and then X-Ray diffraction (XRD) to observe the crystal phases. To validate the methodology, Pt-coated PTL materials have been used as anode for the borohydride oxidation reaction (BOR) in a direct borohydride fuel cell (DBFC) and compared to a state-of-the-art nickel electrode. There is an optimum loading of platinum (below 0.16 mg Pt/cm2) which constitutes the best compromise between power density and faradic efficiency for the borohydride oxidation reaction (BOR). Thanks to this low Pt loading, hydrogen evolved during the anodic reaction is completely valorized. These electrodes combine the advantages of high-performance with a very low metal loading, hence lowering materials cost.
A one dimensional (1-D), isothermal model for a direct methanol fuel cell (DMFC) is presented. This model accounts for the kinetics of the multi-step methanol oxidation reaction at the anode. Diffusion and crossover of methanol are modeled and the mi
Micro-solid oxide fuel cells based on thin films have strong potential for use in portable power devices. However, devices based on silicon substrates typically involve thin-film metallic electrodes which are unstable at high temperatures. Devices ba
The neutronic properties of Molten Salt Reactor are different from that of traditional solid-fuel reactors due to its nuclear fuel particularity. Based upon MCNP code, the influence of the size and shape of fuel salt channel on neutron physics of MSR
Additive manufacturing represents a revolution due to its unique capabilities for freeform fabrication of near net shapes with strong reduction of waste material and capital cost. These unfair advantages are especially relevant for expensive and ener
In this letter, we report a chemical route for synthesizing SiO2@Au core-shell nanoparticles. The process includes four steps: i) preparation of the silica cores, ii) grafting gold nanoparticles over SiO2 cores, iii) priming of the silica-coated gold