CONICET | Buscador de Institutos y Recursos Humanos

Ordered nanoporous carbon CMK-1 was synthesized via a two step; impregnation of the mesopores of MCM-48 with a solution of sucrose using an incipient wetness method. The sucrose?silica composite was then heated at 1173 K for 4 h under nitrogen flow to complete the carbonization. The silica template was dissolved with 5 wt% hydrofluoric acid at room temperature in order to remove the silica. The template-free carbon product thus obtained was filtered, washed with deionized water and ethanol, and dried.Ni-CMK-1 and Zn-CMK-1 were prepared by wet impregnation using NiCl2.6H2O and Zn(NO3) 2.6H2O as source of Ni and Zn respectively. In order to increase the amount of hydrogen adsorbed the sample Zn-CMK-1 was treated under H2 flow, at 1173 K (H2-Zn-CMK-1). Porous carbon CMK-1 and the samples modified with metals were characterized by XRD, FTIR, XPS, BET and SEM. These studies indicate that it was possible to obtain a CMK-1 replica successfully CMK-1 from MCM-48, using sucrose as a carbon precursor.In the XRD pattern of CMK-1 (10º-60º 2 Theta), we observed two diffraction planes (0 0 2) and (1 0 0) that are typical of graphite. Moreover, in the XRD pattern of Zn-CMK-1 we observed ZnO characteristic peaks corresponding to the indices (100), (002), (101), (102), (110), (103), (200), (112) and (201). This indicated that ZnO particles possessed polycrystalline hexagonal wurtzite structure. On the other hand, the XRD pattern of Ni-CMK-3 exhibited peaks of metallic Ni, 44º, 51º and 76º corresponding to the planes (1 0 1), (2 0 0) and (2 2 0).Measurements of hydrogen adsorption at cryogenic temperatures and low pressures were performed. Zn-CMK-1 and Ni-CMK-1 had a lower hydrogen storage capacity than the carbon nanostructured CMK-1. While the sample that was thermally treated under hydrogen flow showed a greater H2 than the sample CMK-1.

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