Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2014-08-01

Journal: JOURNAL OF SUPERCRITICAL FLUIDS

Included Journals: EI、SCIE

Volume: 92

Page Number: 100-106

ISSN: 0896-8446

Key Words: Supercritical CO2; Ag nanowires; Ethylene glycol; Non-equilibrium sorption

Abstract: Well-defined Ag nanowires were obtained in SBA-15 at a short deposition time of 5 min in supercritical CO2 when adding a small amount of ethylene glycol as the co-solvent. Ethylene glycol played a key role in dictating the nanowire morphology. Through detailed investigation of the whole deposition process, including the dissolution of precursor assisted by the co-solvent, the diffusion properties of the precursor into the nano-scale channels of the substrate, and the interaction between the precursor and the substrate, we found that a small amount of precursors were reduced into Ag-0 by ethylene glycol at the initial stage of the deposition. The resultant Ag-0 then acted as nuclei leading to a non-equilibrium sorption of the precursor. The rapid adsorption of the precursor onto the substrate resulted in a high loading of Ag in a short deposition time and the formation of nanowire morphology. Furthermore, this method was successfully extended to other porous substrates such as gamma-Al2O3, SiO2 and KIT-6, demonstrating its great potentials in the synthesis of nanocomposites. (C) 2014 Elsevier B.V. All rights reserved.