A composite Sb-doped SnO2 electrode based on the TiO2 nanotubes prepared by hydrothermal synthesis

H. Xu, Q. Zhang, W. Yan, Wei Chu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

A hydrothermal synthesis approach was adopted to embed Sb-doped SnO2 into TiO2 nanotubes to form a three dimensional electrode(TiO2-NTs/SnO2-Sb), and it was compared with the conventionally fabricated Ti/SnO2-Sb2O5 electrode(Sb-doped SnO2 coated Ti sheet) in terms of surface morphology, crystal structure, photoelectrochemical properties and organic degradation performances. It was clearly observed from SEM images that the TiO2-NTs/SnO2-Sb electrode had a compact surface and the Sb-doped SnO2 oxide was embedded successfully into the TiO2 nanotubes. The loading amount of Sb-SnO2 in the TiO2 nanotube electrode was therefore increased compared with that in the Ti/SnO2-Sb electrode, which is beneficial for the electrochemical performance. The hydrothermally synthesized electrode has much better and larger SnO2 crystals than that prepared by the traditional dip-coating method according to the Scherrer's equation derived from the XRD analysis. Besides, the durability of the TiO2-NTs/SnO2-Sb electrode was tested to be 116 hours, which was much longer than that of the Ti/SnO2-Sb electrode (1.6 hours), suggesting a long service lifetime electrode was achieved through the hydrothermal method. A higher oxygen evolution potential leading to a preferred degradation of methyl orange in an electro-catalytic process was observed by using the hydrothermally-prepared electrode than that of Ti/SnO2-Sb electrode. The TiO2-NTs/SnO2-Sb electrode has a superior ability in coupling the advantages of photocatlysis and electrocatalysis, which was evidenced by the linear sweep voltammetry and the chronoamperometry tests. It was interesting to note that an irradiation from Xenon lamp originally has no effect on the probe dye's removal. However, as the same irradiation was introduced to the electrocatalysis process using the TiO2-NTs/SnO2-Sb electrode, the removal efficiency of the probe significantly increased form 15.7% to 26.9% in 2 hours, due to a synergetic effect.
Original languageEnglish
Pages (from-to)6639-6652
Number of pages14
JournalInternational Journal of Electrochemical Science
Volume6
Issue number12
Publication statusPublished - 2011

Keywords

  • TiO2 nanotubes
  • Hydrothermal synthesis
  • Sb-doped SnO2
  • Electrocatalysis
  • Photoelectrocatalysis

ASJC Scopus subject areas

  • Electrochemistry

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