Facet-dependent carrier dynamics of cuprous oxide regulating the photocatalytic hydrogen generation

Cui Ying Toe, Marlene Lamers, Thomas Dittrich, Hassan A. Tahini, Sean C. Smith, Jason Scott, Rose Amal, Roel Van De Krol, Fatwa F. Abdi*, Yun Hau Ng*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

The intrinsic carrier dynamics of cuprous oxide (Cu2O) are known to have a crucial influence on photocatalytic performances. The photoactivity of rhombic dodecahedral Cu2O with dominant {110} facets (RD-Cu2O) is demonstrated to surpass that of cubic Cu2O with {100} surfaces (CB-Cu2O). Time resolved microwave conductivity (TRMC) measurements reveal the higher carrier mobility of RD-Cu2O when compared to CB-Cu2O. Additionally, modulated surface photovoltage (SPV) measurements further supported the better charge separation efficiency of RD-Cu2O. Although CB-Cu2O exhibited more pronounce SPV signals, the homogeneous distribution of electrical fields drives the majority charge inward and led to detrimental charge recombination. In contrast, the weak SPV signals for RD-Cu2O were attributed to a modulated distribution of charges towards the facets and facet boundaries, demonstrating a better charge separation. This study shows that carrier dynamics and defect density should also be regarded as facet-dependent properties that can have deciding influence on the photocatalytic activity.

Original languageEnglish (US)
Pages (from-to)2200-2212
Number of pages13
JournalMaterials Advances
Volume3
Issue number4
DOIs
StatePublished - Feb 21 2022

Bibliographical note

Publisher Copyright:
© The Royal Society of Chemistry.

ASJC Scopus subject areas

  • Chemistry (miscellaneous)
  • General Materials Science

Fingerprint

Dive into the research topics of 'Facet-dependent carrier dynamics of cuprous oxide regulating the photocatalytic hydrogen generation'. Together they form a unique fingerprint.

Cite this