The heat annealing effect on the performance of CdS/CdSe-sensitized TiO2 photoelectrodes in photochemical hydrogen generation

Ching Fa Chi, Shih Yi Liau, Yuh Lang Lee

Research output: Contribution to journalArticle

71 Citations (Scopus)

Abstract

Heat treatment was utilized to anneal the semiconductor sensitizers (CdS, CdSe and CdS/CdSe) assembled on mesoporous TiO2 films to enhance the performance of the photoelectrodes in a process of photoelectrochemical hydrogen generation. Various annealing temperatures (150, 300 and 400 °C) were employed and the results show that appropriately elevating the temperature (to approx. 300 °C) can increase the crystallinity of the CdS and CdSe, improve the charge transport characteristic of a photoelectrode and, therefore, lead to a higher performance of the TiO2 /CdS and TiO2 /CdSe electrodes. However, an over-annealing temperature (400 °C) may cause serious oxidation and/or decomposition of the sensitizers which is unfavorable to the photoelectrode. For the co-sensitized electrode, counter-diffusion of CdS and CdSe happens at the CdS/CdSe interface when the TiO2 /CdS/CdSe electrode was co-annealed at 300 °C, which significantly decreases the performance of the co-sensitized electrode. This problem was solved by annealing first a TiO2 /CdS electrode at 300 °C, followed by CdSe assembly and a second annealing at 150 °C. This electrode appears to have better performance than the others.

Original languageEnglish
Article number025202
JournalNanotechnology
Volume21
Issue number2
DOIs
Publication statusPublished - 2010 Jan 1

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'The heat annealing effect on the performance of CdS/CdSe-sensitized TiO<sub>2</sub> photoelectrodes in photochemical hydrogen generation'. Together they form a unique fingerprint.

  • Cite this