Cocatalyst-free photocatalysts for efficient visible-light-induced H 2 production: Porous assemblies of CdS quantum dots and layered titanate nanosheets

Hyo Na Kim, Tae Woo Kim, In Young Kim, Seong Ju Hwang

Research output: Contribution to journalArticle

162 Citations (Scopus)

Abstract

Highly efficient, visible-light-induced H2 generation can be achieved without the help of a Pt cocatalyst by new hybrid photocatalysts, in which CdS quantum dots (QDs) (particle size ≈2.5 nm) are incorporated in the porous assembly of sub-nanometer-thick layered titanate nanosheets. Due to the very-limited crystal dimension of component semiconductors, the electronic structure of CdS QDs is strongly coupled with that of the layered titanate nanosheets, leading to an efficient electron transfer between them and the enhancement of the CdS photostability. As a consequence of the promoted electron transfer, the photoluminescence of CdS QDs is nearly quenched after hybridization, indicating the almost-suppression of electron-hole recombination. These Pt-cocatalyst-free, CdS-layered titanate nanohybrids show much-higher photocatalytic activity for H2 production than the precursor CdS QDs and layered titanate, which is due to the increased lifetime of the electrons and holes, the decrease of the bandgap energy, and the expansion of the surface area upon hybridization. The observed photocatalytic efficiency of these Pt-free hybrids (≈1.0 mmol g-1 h-1) is much greater than reported values of other Pt-free CdS-TiO2 systems. This finding highlights the validity of 2D semiconductor nanosheets as effective building blocks for exploring efficient visible-light-active photocatalysts for H 2 production.

Original languageEnglish
Pages (from-to)3111-3118
Number of pages8
JournalAdvanced Functional Materials
Volume21
Issue number16
DOIs
Publication statusPublished - 2011 Aug 23

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Electrochemistry

Fingerprint Dive into the research topics of 'Cocatalyst-free photocatalysts for efficient visible-light-induced H <sub>2</sub> production: Porous assemblies of CdS quantum dots and layered titanate nanosheets'. Together they form a unique fingerprint.

  • Cite this