• About
  • Policies
  • What is open access
  • Library
  • Contact
Advanced search
      View Item 
      •   BUIR Home
      • Scholarly Publications
      • Faculty of Science
      • Department of Chemistry
      • View Item
      •   BUIR Home
      • Scholarly Publications
      • Faculty of Science
      • Department of Chemistry
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.

      The effect of anions of transition metal salts on the structure of modified mesostructured silica films and monoliths

      Thumbnail
      View / Download
      694.2 Kb
      Author(s)
      Demirörs, A. F.
      Arslan, M.
      Dag, Ö.
      Date
      2007
      Source Title
      Microporous and Mesoporous Materials
      Print ISSN
      1387-1811
      Publisher
      Elsevier
      Volume
      98
      Issue
      1-3
      Pages
      249 - 257
      Language
      English
      Type
      Article
      Item Usage Stats
      137
      views
      92
      downloads
      Abstract
      The structure of the preformed LC mesophase of water:transition metal salt ([M(H2O)6]X2):acid (HX):oligo(ethylene oxide) (or Pluronics):tetramethylorthosilicate (TMOS) mixture during hydrolysis and partial polymerization of the silica source is maintained upon further polymerization and condensation of the silica species in the solid state. The liquid mixture in early stage of the silica polymerization could be casted or dip coated to a surface of a glass or silicon wafer to produce mesostructured silica monoliths and films, respectively. The silica species and ions (metal ions and anions) influence the structure of the LC mesophases (as a result, the structure of silica) and the hydrophilic and hydrophobic balance in the reaction media. The silica structure can be changed from hexagonal to cubic by increasing, for example, the nitrate salt concentration in the nitrate salt systems. A similar transformation takes place in the presence of very low perchlorate salt concentration. The salt concentration in the mesostructured silica can be increased up to 1.1/1.0 salt/SiO2 w/w ratio, in mesostructured silica materials by maintaining its lamella structure in P123 and cubic in the CnEOm systems. However, the materials obtained from the P123 systems undergo transformation from lamella to 2D hexagonal upon calcinations. The method developed in this work can be used to modify the internal surface of the pores with various transition metal ions and metal oxides that may find application in catalysis. © 2006 Elsevier Inc. All rights reserved.
      Keywords
      Liquid crystals
      Mesostructured
      Non - ionic surfactants
      Pluronics
      Transition metal ions
      Hydrolysis
      Hydrophobicity
      Salts
      Polymerization
      Silicon wafers
      Surface active agents
      Permalink
      http://hdl.handle.net/11693/23563
      Published Version (Please cite this version)
      http://dx.doi.org/10.1016/j.micromeso.2006.09.004
      Collections
      • Department of Chemistry 640
      Show full item record

      Browse

      All of BUIRCommunities & CollectionsTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartmentsThis CollectionTitlesAuthorsAdvisorsBy Issue DateKeywordsTypeDepartments

      My Account

      LoginRegister

      Statistics

      View Usage StatisticsView Google Analytics Statistics

      Bilkent University

      If you have trouble accessing this page and need to request an alternate format, contact the site administrator. Phone: (312) 290 1771
      © Bilkent University - Library IT

      Contact Us | Send Feedback | Off-Campus Access | Admin | Privacy