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In the present paper, an experimental study of the catalytic decomposition of hydrous hydrazine was investigated on the different structural forms of the catalyst. The synthesized iridium catalysts have been usually used directly and have not been evaluated in the laboratory reactor. This study includes the preparation of iridium-based catalysts supported on spherical (alumina), honeycomb monoliths (cordierite) and foams (alumina) for the evaluation of catalytic activity in the laboratory reactor. The characterizations of these catalysts were evaluated by the TGA, FESEM and BET analysis. The result of the catalytic characterization of monolithic support was shown a homogeneous distribution of active metal without any problem of sintering (average size 25 nm) on the support surface. While the surface of the spherical and foam supports were shown non-uniform distribution of nanoparticles on the support skeleton (average size 55 nm). The monolithic catalyst exhibits higher decomposition rate and H 2 selectivity than other supports due to uniform in shape and particle size distribution.

Here, we present the synthesis and characterization of low-density Multi-walled carbon nanotube (MWCNT) /carbon (CA) aerogel by creating a three-dimensional assembly of carbon nanotubes (CNTs) in Polyacrylonitrile (PAN)/Dimethyl formamide(DMF) solution to create a stable gel, followed by a CO2 supercritical drying. Aerogels with varying nanotube loading (0-25 wt. %) and density (50-500mg cm -3 ) were fabricated and characterized by optical microscopy, electron microscopy, nitrogen sorption and electrical conductivity analysis. Physical properties of the MWNT/CA composites were highly dependent upon nanotube loading. The data indicate that the shrinkage value decreases gradually during drying and pyrolysis process when MWCNT content increases in formulations. Surface area as high as 735 m 2 /g was achieved for MWNT/PAN aerogel with carbon nanotube loading higher than 20 wt. % .

In this paper, the development and application of a novel carbon nanotube/Polycitric acid (MWCNT-graft-PCA-Pt) nanocomposite as an efficient nanocatalyst for PEM fuel cell is reported. Covalent attachment to PCA agents is the main method for the modification of CNTs with polymers. By this method electrocatalysts with a narrow particle-size distribution and good dispersion have been produced. Carbon nanotube (CNT) film electrodes have been fabricated by a novel process involving the electrostatic spray deposition (ESD) of a CNT solution. The CNT film electrodes have shown well-entangled and interconnected porous structures with good adherence to the substrate. Cyclic voltammograms (CV) of catalysts using the spongy thin layer electrode technique were obtained for the catalysts surface at evaluation and for Methanol Oxidation reaction (MOR). CV results have demonstrated that the current density and MOR activity of the MWCNT-graft-PCA-Pt is respectively higher than of the MWCNT-Pt nanocatalyst.

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