Ordered micro-porous carbon molecular sieves containing well-dispersed platinum nanoparticles for hydrogen storage

Ordered micro-porous carbon molecular sieves containing highly dispersed platinum nanoparticles with tunable sizes from I to 6 non are synthesized in this work. The synthesis is simply realized by nanocasting of furfuryl alcohol precursor on Pt-impregnated NaY zeolite hard templates and complemented by chemical vapor deposition by propylene gas. During the carbonization, Pt ions can be reduced to form highly dispersed Pt nanoparticles on the carbon matrixes. This method allows a very high Pt-loading up to 40 wt % while maintaining a high metal dispersion. X-ray diffraction and transmission electron microscopy measurements reveal the existence of uniformly dispersed Pt nanoparticles and microstructural regularity. Nitrogen adsorption isotherms show that the ordered micro-porous carbon molecular sieves possess a high surface area around 2750 m(2)/g, large micro-pore volume 1.38 cm(3)/g, and narrow pore size distribution (similar to 1 nm) in the micropore-range. A high hydrogen uptake up to 2.8 wt% at 77 K and I bar is observed. A high and relatively homogeneous value of hydrogen adsorption heat 11 kJ/mol in 1% Pt contained carbon was obtained, which exceeds the literature reported Values for other carbon based adsorbents or metal organic framework compounds and is very close to the optimal value, 15 kJ/mol, recommended in the literature, Suggesting a great potential for hydrogen storage or fuel cell applications. (C) 2008 Elsevier Inc. All rights reserved,