The use of Cs0.5H0.5PW12O40 insoluble salt as a superacid promoter in the catalyst layer of a polymer electrolyte membrane fuel cell (PEMFC) has been investigated. An increase of performance has been recorded at intermediate temperatures (110–130 °C) and under low relative humidity (R.H.). The promoter appears to mitigate the ionomer dry-out effects in the catalytic layer and produces an increa...

The beautiful target and spiral patterns exhibited by the Belousov-Zhabotinsky (BZ) reaction in thin films of solution are representative of spatiotemporal behavior in a two-dimensional, planar excitable medium. 14 We report here BZ chemical waves propagating on the two-dimensional surface of a sphere. Singleand double-rotor spiral waves develop on the surface of a single cation exchange bead, ...

The photocatalytic degradation of organic compounds of olive mill wastewater (OMWW) was investigated by using core-shell-shell Fe3O4/SiO2/TiO2 nanoparticles as catalyst. The preparation of nanoparticles was performed by coating onto magnetic nanoparticles a SiO2 layer, using Stober method and TiO2 layer, using sol-gel method. The photo catalyst was characterized by dynamic light scattering (DLS...

Carbon nanotubes (CNTs) have been studied extensively because of their outstanding electrical, mechanical and thermal properties. A common way to integrate CNTs in microsystems is to “grow” them from a catalyst layer using Chemical Vapour Deposition (CVD) [1]. The shape of the microstructures is controlled by patterning the thin catalyst layer which agglomerates to form catalyst nanoparticles. ...

Quantum chemical molecular dynamics simulations of graphene nucleation on the Ni(111) surface show that graphene creates its own step-edge as it forms. This "step-edge self-assembly" is driven by the formation of thermodynamically favorable Ni-C σ-bonds at the graphene edge. This dynamic aspect of the Ni(111) catalyst is in contrast to the commonly accepted view that graphene nucleates on a pre...

This paper represents the lowest growth temperature for silicon nano-wires (SiNWs) via a vapour-liquid-solid method, which has ever been reported in the literature. The nano-wires were grown using plasma-enhanced chemical vapour deposition technique at temperatures as low as 150°C using gallium as the catalyst. This study investigates the structure and the size of the grown silicon nano-structu...

PtRu/Ti anodes with varying Pt ratio Ru ratio were prepared by electrodeposition of a thin PtRu catalyst layer onto Ti mesh for a direct methanol fuel cell (DMFC). The morphology and structure of the catalyst layers were analyzed by SEM, EDX and XRD. The catalyst coating layer shows an alloy character. The relative activities of the PtRu/Ti electrodes were assessed and compared in half cell and...

The gas diffusion layer (GDL) is an essential element of the electrodes in polymer electrolyte membrane (PEM) fuel cells. The GDL makes electrical contact with the catalyst layers to provide a larger area to carry the electronic current from the catalyst to the bipolar plates reducing the resistance for current flow. The GDL must be porous to permit the flow of reactant gas from the gas flow ch...

here, we have synthesized vertically aligned carbon nanotubes (va-cnts), using chemical vapor deposition (cvd) method. cobalt and ethanol are used as the catalyst and the carbon source, respectively. the effects of ethanol flow rate, thickness of co catalyst film, and growth time on the properties of the carbon nanotube growth are investigated. the results show that the flow rate of ethanol and...