Incorporation of Co nanoparticles over MCM-41 supports using supercritical CO2

S. ASPROMONTE; A. SASTRE; E. ALONSO; E. MIRÓ; A. BOIX; M. J. COCERO

Valencia

Conferencia; 5th International FEZA Conference: Innovations in zeolites and ordered porous solids; 2011

Spanish Zeolite Group-Federation of European Zeolite Associations,

In the literature, it can be found that MCM41 is an interesting material for catalyst support,due to its regular, hexagonal mesoporous structure (with uniform pore openings of 15–100 Å)and the potential modification of its properties by introduction of specific transition metalcations or metal complexes [1]. Attempts to insert transition metals, such as Cu [2], Ti, Cr,Mn or Fe into the MCM41 framework have been reported recently [1] and the incorporationof these has been commonly performed by wet impregnation and co-precipitation [3]. Analternative approach involves the dissolution of an organometallic precursor in supercriticalcarbon dioxide (scCO2), and its subsequent decomposition over the mesoporous support. Thistechnique, that is called supercritical fluid deposition (SFD), takes advantage of the excellentphysical properties of scCO2 which are tunable with small variations of P and/or T. The zerosurface tension of scCO2 allows better penetrating and wetting of pores than liquid solvents.Simple removal from the substrate by depressurization avoids problems of solvent residues orpore collapse on drying.This work presents the deposition of Co nanoparticles directly onto MCM41 and Al-MCM41mesoporous matrix by the decomposition of cobaltocene (CoCp2) in supercritical carbondioxide. Different characterization techniques such as SEM/EDX, SAXS and Laser RamanSpectroscopy (LRS) were employed.