The deposition of Ni nanoparticles into porous supports is very important in catalysis. In this paper, we explore the use of supercritical CO(2) (scCO(2)) as a green solvent to deposit Ni nanoparticles on mesoporous SiO2 SBA-15 and a carbon xerogel. The good transport properties of scCO(2) allowed the efficient penetration of metal precursors dissolved in scCO(2) within the pores of the support without damaging its structure.
View Article and Find Full Text PDFThe effect of supercritical CO(2) (scCO(2)) in 3D latex arrays formed by monodispersed particles of polystyrene (PS), PS cross-linked with divinylbenzene (PS-DVB), and PS block copolymers with 2-hydroxyethyl methacrylate (PS-HEMA), methacrylic acid (PS-MA), acrylic acid (PS-AA), itaconic acid (PS-IA), and a mixture of methacrylic and itaconic acid (PS-IA-MA) has been studied. Sorption of CO(2) into the polymer particles leads to a decrease in the glass transition temperature of the polymer and the swelling of the particles and induces their coalescence. 3D-latex arrays of the former compositions were treated in scCO(2) at temperatures and pressures ranging from 40 to 80 degrees C and from 85 to 197 bar, respectively.
View Article and Find Full Text PDFOrdered macroporous SiO(2) membranes were produced by the decomposition of silicon alkoxides in supercritical carbon dioxide (scCO(2)) using 3D-latex arrays as templates.
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