Binder-free Cu/Cu2O/CuO/Pd nanorods photoelectrode for regulating the faradaic efficiency for acetaldehyde and acetate production during photoelectrochemical CO2RR by stabilizing the Cu2O phase

Periyayya Uthirakumar, Yeji Lee, Hoki Son, Vandung Dao, Chi Yeop Kim, In Hwan Lee

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

The development of efficient photoelectrodes to accelerate photoelectrochemical carbon dioxide reduction reaction (PEC-CO2RR) to obtain value-added chemicals or fuels is remarkably significant. Although Cu2O-based three-dimensional (3D) heterojunctions have emerged as promising materials for the selective generation of C2 products, they are still plagued by the stability of Cu+ in the Cu2O phase. In this work, we developed a binder-free Cu/Cu2O/CuO/Pd nanorods heterojunction via simple oxidation/reduction procedures to stabilize Cu+ in the Cu2O phase by incorporating high-work function Pd nanoparticles as a co-catalyst. The incorporated Pd not only stabilizes Cu+ through charge transfer from Cu2O to Pd but also enhances the stability of the *CO intermediate to improve C–C coupling for the formation of the C2 products, primarily acetate, and acetaldehyde. The Cu/Cu2O/CuO/Pd photoelectrode exhibits a superior Faradaic efficiency (FE) to produce acetate (21.4%) acetate and acetaldehyde (20.8%) at a negative potential of − 1.4 V (vs RHE), which are 3.5 and 19 times higher than that of Cu/Cu2O/CuO photoelectrode. Moreover, the Cu/Cu2O/CuO photoelectrode produces a maximum hydrogen gas evolution of ∼70% at − 1.2 V (vs RHE). Furthermore, compared to the Cu/Cu2O/CuO photoelectrode, the Cu/Cu2O/CuO/Pd photoelectrodes exhibit remarkable stability for a 5-h operation even at a higher negative applied potential of − 1.2 V vs RHE in CO2-saturated 0.1 M KHCO3. The stabilization of the Cu2O (111) phase is confirmed by the appearance of a characteristic X-ray diffraction and X-ray photoelectron peaks after PEC-CO2RR. These results indicate that the proposed high-stability Cu/Cu2O/CuO/Pd photoelectrode provides a new pathway to produce more C2 products of acetaldehyde and acetate.

Original languageEnglish
Article number111253
JournalJournal of Environmental Chemical Engineering
Volume11
Issue number6
DOIs
Publication statusPublished - 2023 Dec

Bibliographical note

Publisher Copyright:
© 2023 Elsevier Ltd

Keywords

  • Acetaldehyde formation
  • CO reduction
  • Cu/CuO/CuO/Pd photoelectrode
  • Nano architectures
  • Photoelectrochemical

ASJC Scopus subject areas

  • Chemical Engineering (miscellaneous)
  • Waste Management and Disposal
  • Pollution
  • Process Chemistry and Technology

Fingerprint

Dive into the research topics of 'Binder-free Cu/Cu2O/CuO/Pd nanorods photoelectrode for regulating the faradaic efficiency for acetaldehyde and acetate production during photoelectrochemical CO2RR by stabilizing the Cu2O phase'. Together they form a unique fingerprint.

Cite this