Charge Separation in Mesoporous Aluminosilicates

Hongxian Han, Michael Paddon-Row, Russell F. Howe

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

EPR spectroscopy has been used to investigate spontaneous and/or photo-induced electron transfer between adsorbed organic molecules and the mesoporous aluminosilicate MCM-41 host. Spontaneous electron transfer occurs from the host to electron acceptor molecules with sufficiently favourable reduction potentials (TCNE, TCNQ; 1;4-benzoquinone, 1,4-naphthaquinone and 1,4-anthraquinone), provided the MCM-41 contains aluminium and the radical anion yield correlates with the aluminium content of the host. The semiquinone radical anions are interacting strongly with exposed Al3+ sites, whereas the TCNE and TCNQ radical anions are loosely bound and can be washed from the host. Radical cation formation is observed when electron donor molecules with favourable oxidation potentials are adsorbed in MCM-41 containing aluminium, and the radical cations formed interact with exposed Al3+ sites. This work shows that aluminium-containing MCM-41 contains both electron donating and electron accepting sites which may intervene in intra-molecular charge separation processes in adsorbed organic molecules.

Original languageEnglish
Pages (from-to)551-564
Number of pages13
JournalResearch on Chemical Intermediates
Volume34
Issue number5-7
DOIs
Publication statusPublished - May 2008

Keywords

  • EPR
  • MCM-41
  • electron transfer
  • radical cation
  • radical anion
  • electron-spin resonance
  • TIMCM-41 molecular-sieves
  • paramagnetic resonance
  • radical cations
  • artificial photosynthesis
  • methyl viologen
  • zeolites
  • ion
  • photoionization

Cite this

Charge Separation in Mesoporous Aluminosilicates. / Han, Hongxian; Paddon-Row, Michael; Howe, Russell F.

In: Research on Chemical Intermediates, Vol. 34, No. 5-7, 05.2008, p. 551-564.

Research output: Contribution to journalArticle

Han, Hongxian ; Paddon-Row, Michael ; Howe, Russell F. / Charge Separation in Mesoporous Aluminosilicates. In: Research on Chemical Intermediates. 2008 ; Vol. 34, No. 5-7. pp. 551-564.
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