Synergistic promotion of solar-driven H2generation bythree-dimensionally ordered macroporous structured TiO2-Au-CdS ternary photocatalyst

Heng Zhao, Min Wu, Jing Liu, Zhao Deng, Yu Li, Bao Lian Su

Research output: Contribution to journalArticlepeer-review

Abstract

A ternary photocatalyst TiO2-Au-CdS based on three-dimensionally ordered macroporous TiO2(3DOM TiO2) was successfully prepared to enhance the light absorption, extend the light responsive region,reduce the recombination rate of charge carriers and promote the efficiency of water splitting H2evolution ultimately. The obtained 3DOM TiO2-Au-CdS powder has a pure anatase phase of TiO2 and greenockite structured CdS according to the XRD results and TEM analysis. Au nanoparticles (AuNPs) andCdS were evenly distributed in the 3DOM structure which enhances H2-generation rate under visible lightby improving light harvesting and utilizing its mass transfer facilitation. As a result, the hydrogen gen-eration rate (1.81 mmol h-1 g-1) using 3DOM TiO2-Au-CdS photocatalyst under visible light irradiationwas 13-fold higher than the binary 3DOM TiO2-CdS reference photocatalyst. Under ultraviolet-visiblelight, the photogenerated electrons in TiO2 would be transferred to recombine with the holes of CdS andunder visible light, electrons would move to the conduction band (CB) of TiO2 from CdS via AuNPs. Thetwo different types of internal electron-transfer process in the ternary photocatalyst under ultravioletand visible light were proposed respectively and both would efficiently reduce the recombination rateof photogenerated electrons and holes thus stimulate H2 evolution rate. The present work demonstratedan excellent example of the synergistic effect of the light absorption enhancement by 3DOM structure,the photosensitizing and electron reservoir effect of AuNPs and the reduction of recombination rate ofcharge carriers by CdS to highly promote the photocatalytic activity in water splitting reaction.

Original languageEnglish
Pages (from-to)182-190
Number of pages9
JournalApplied Catalysis B: Environmental
Volume184
DOIs
Publication statusPublished - 1 May 2016

Keywords

  • 3DOM
  • Au nanoparticles
  • CdS
  • Efficient electron transfer
  • H evolution
  • TiO

Fingerprint

Dive into the research topics of 'Synergistic promotion of solar-driven H<sub>2</sub>generation bythree-dimensionally ordered macroporous structured TiO<sub>2</sub>-Au-CdS ternary photocatalyst'. Together they form a unique fingerprint.

Cite this