EPR of O-2(-) radicals in the zeolites NH4NaY and NH(4)CaA


Koksal F., Ucun F.

ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES, vol.53, no.12, pp.951-954, 1998 (Peer-Reviewed Journal) identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 12
  • Publication Date: 1998
  • Journal Name: ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.951-954

Abstract

Activated and non-activated states of the zeolites NH4NaY and NH(4)CaA, and their NH; forms were prepared with an (NH4)(2)SO4 solution and were investigated by EPR after gamma-irradiation. The formed radicals were attributed to O-2(-) supposed to be trapped near a trigonally coordinated framework of Al-27(27)(I = 5/2). Anisotropic O-2(-) spectra were observed, consisting of hyperfine structure due to the Al framework, even at room temperature. This was attributed to the scarceness of NH4+ sites or trap sites because of the preparation of the NH4+ forms of the zeolites with an (NH4)(2)SO4 solution. The crystal field splittings were found and interpreted.