B. Viswanathan

Surface acidity of MCM-41 by in situ IR studies of pyridine adsorption

Abstract The nature and concentration of the acid sites of MCM-41 material as a function of Si/Al ratio have been monitored by in situ IR using pyridine as a probe molecule. The thermal stability of aluminium in the framework of these materials is studied using 27 Al MAS NMR spectroscopy. The tetrahedral to octahedral aluminium ratio is found to increase with higher aluminium incorporation. The sample with the lowest Si/Al ratio is found to exhibit higher acidity compared to the other samples. However, the acidity of these mesoporous aluminosilicates is less compared to the conventional H–Y zeolite.

Conducting polymeric nanotubules as high performance methanol oxidation catalyst support

Pt nanoparticle-supported conducting nanotubules of polypyrrole prepared by a template method exhibited excellent catalytic activity and stability for the electrooxidation of methanol in comparison to Pt supported on conventionally synthesised conducting polypyrrole.

Pt supported on Polyaniline-V2O5 nanocomposite as the electrode material for methanol oxidation

The nanocomposite material prepared via the intercalation of polyaniline in matrix has been used as the support for Pt in methanol oxidation reaction. The average particle size of the Pt as evaluated from the high-resolution transmission electron microscope was found to be 4 nm. The X-ray photoelectron spectroscopy analysis revealed that vanadium is present in the form of and Pt in the metallic state. The activity of methanol oxidation of the Pt loaded nanocomposite electrode as evaluated from cyclic voltammetry was found to be at vs. Ag/AgCl for a Pt loading of The chronoamperometric response reveals the better activity and stability of the nanocomposite electrode compared to the bulk Pt electrode.

Preparation of Pt-Ru bimetallic catalyst supported on carbon nanotubes

The template carbonization of polyphenyl acetylene yields hollow, uniform cylindrical carbon nanotubes with outer diameter almost equal to pore diameter of the template used. High resolution transmission electron microscopic investigation reveals that Pt-Ru nanoparticles are highly dispersed inside the tube with an average particle size of 1.7 nm.

Synthesis and characterization of mesoporous SAPO

Self-assembled ordered cetyltrimethylammonium bromide (CTAB) is used as a template for the synthesis of mesoporous silicoaluminophosphates with varying Si/Al ratio.