Facile ion-exchanged synthesis of Sn 2+ incorporated potassium titanate nanoribbons and their visible-light-responded photocatalytic activity
Abstract
Sn 2+-incorporated potassium titanate (K 2Ti 6O 13) nanoribbons were prepared by a facile acid-free ion-exchanged method in a dehydrated methanol solution at room temperature. XRD patterns suggested that K 2Ti 6O 13 (KTO) and Sn 2+-incorporated KTO (SKTO) are well crystallized with monoclinic phase structures. The mole ratio of incorporated Sn 2+ to K + in SKTO was estimated to be 2. X-ray photoelectron spectrum showed that the Sn species of SKTO consisted of 90% of Sn 2+ and 10% of Sn 4+, suggesting that part of Sn 2+ was oxidized to Sn 4+ in the incorporation process. The band gap of SKTO was 0.7 eV narrower than that of KTO, which was derived from lift of the top of the valence band due to the hybridization of Sn5s and O2p orbitals. The SKTO nanoribbons showed remarkable photocatalytic activities for H 2 evolution and rhodamine B degradation under visible light irradiation ( λ ≥ 420 nm). The photocatalytic mechanism and durability were studied in detail. The advantage of this acid-free ion-exchange method is ease of ion-exchange of K + with H + and maintenance of the integrity of the 1D nanoribbon structures. This method can be applied to preparation of other Sn 2+-incorporated compounds with special nanostructures.
- Publication:
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International Journal of Hydrogen Energy
- Pub Date:
- January 2011
- DOI:
- 10.1016/j.ijhydene.2011.01.082
- Bibcode:
- 2011IJHE...36.4716L
- Keywords:
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- Potassium titanate nanoribbons;
- Acid-free ion-exchange method;
- Sn(II) incorporation;
- Photocatalytic H <SUB loc="post">2</SUB> evolution;
- RhB photo-degradation