Highly stable copper oxide composite as an effective photocathode for water splitting via a facile electrochemical synthesis strategy

Handle URI:
http://hdl.handle.net/10754/561995
Title:
Highly stable copper oxide composite as an effective photocathode for water splitting via a facile electrochemical synthesis strategy
Authors:
Zhang, Zhonghai; Wang, Peng ( 0000-0003-0856-0865 )
Abstract:
Hydrogen generation through photoelectrochemical (PEC) water splitting using solar light as an energy resource is believed to be a clean and efficient way to overcome the global energy and environmental problems. Extensive research effort has been focused on n-type metal oxide semiconductors as photoanodes, whereas studies of p-type metal oxide semiconductors as photocathodes where hydrogen is generated are scarce. In this paper, highly efficient and stable copper oxide composite photocathode materials were successfully fabricated by a facile two-step electrochemical strategy, which consists of electrodeposition of a Cu film on an ITO glass substrate followed by anodization of the Cu film under a suitable current density and then calcination to form a Cu 2O/CuO composite. The synthesized Cu 2O/CuO composite was composed of a thin layer of Cu 2O with a thin film of CuO on its top as a protecting coating. The rational control of chemical composition and crystalline orientation of the composite materials was easily achieved by varying the electrochemical parameters, including electrodeposition potential and anodization current density, to achieve an enhanced PEC performance. The best photocathode material among all materials prepared was the Cu 2O/CuO composite with Cu 2O in (220) orientation, which showed a highly stable photocurrent of -1.54 mA cm -2 at a potential of 0 V vs reversible hydrogen electrode at a mild pH under illumination of AM 1.5G. This photocurrent density was more than 2 times that generated by the bare Cu 2O electrode (-0.65 mAcm -2) and the stability was considerably enhanced to 74.4% from 30.1% on the bare Cu 2O electrode. The results of this study showed that the top layer of CuO in the Cu 2O/CuO composite not only minimized the Cu 2O photocorrosion but also served as a recombination inhibitor for the photogenerated electrons and holes from Cu 2O, which collectively explained much enhanced stability and PEC activity of the Cu 2O/CuO composite. Thus, the electrochemical strategy proposed in this study for the synthesis of the Cu 2O/CuO composite opens a new way to use copper oxides as photocathode materials in PEC cells for a highly stable and effective water splitting. © 2012 The Royal Society of Chemistry.
KAUST Department:
Water Desalination and Reuse Research Center (WDRC); Biological and Environmental Sciences and Engineering (BESE) Division; Environmental Science and Engineering Program; Water Desalination & Reuse Research Cntr; Environmental Nanotechnology Lab
Publisher:
Royal Society of Chemistry
Journal:
Journal of Materials Chemistry
Issue Date:
2012
DOI:
10.1039/c1jm14478b
Type:
Article
ISSN:
09599428
Sponsors:
This work was supported by the KAUST Baseline Fund. We thank Drs Lan Zhao, Bei Zhang, and Mohamed Nejib Hedhili from King Abdullah University of Science and Technology (KAUST) for their help with SEM, XRD, and XPS, respectively. Z.Z is grateful for Sabic Postdoctoral Fellowship.
Appears in Collections:
Articles; Environmental Science and Engineering Program; Water Desalination and Reuse Research Center (WDRC); Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorZhang, Zhonghaien
dc.contributor.authorWang, Pengen
dc.date.accessioned2015-08-03T09:35:51Zen
dc.date.available2015-08-03T09:35:51Zen
dc.date.issued2012en
dc.identifier.issn09599428en
dc.identifier.doi10.1039/c1jm14478ben
dc.identifier.urihttp://hdl.handle.net/10754/561995en
dc.description.abstractHydrogen generation through photoelectrochemical (PEC) water splitting using solar light as an energy resource is believed to be a clean and efficient way to overcome the global energy and environmental problems. Extensive research effort has been focused on n-type metal oxide semiconductors as photoanodes, whereas studies of p-type metal oxide semiconductors as photocathodes where hydrogen is generated are scarce. In this paper, highly efficient and stable copper oxide composite photocathode materials were successfully fabricated by a facile two-step electrochemical strategy, which consists of electrodeposition of a Cu film on an ITO glass substrate followed by anodization of the Cu film under a suitable current density and then calcination to form a Cu 2O/CuO composite. The synthesized Cu 2O/CuO composite was composed of a thin layer of Cu 2O with a thin film of CuO on its top as a protecting coating. The rational control of chemical composition and crystalline orientation of the composite materials was easily achieved by varying the electrochemical parameters, including electrodeposition potential and anodization current density, to achieve an enhanced PEC performance. The best photocathode material among all materials prepared was the Cu 2O/CuO composite with Cu 2O in (220) orientation, which showed a highly stable photocurrent of -1.54 mA cm -2 at a potential of 0 V vs reversible hydrogen electrode at a mild pH under illumination of AM 1.5G. This photocurrent density was more than 2 times that generated by the bare Cu 2O electrode (-0.65 mAcm -2) and the stability was considerably enhanced to 74.4% from 30.1% on the bare Cu 2O electrode. The results of this study showed that the top layer of CuO in the Cu 2O/CuO composite not only minimized the Cu 2O photocorrosion but also served as a recombination inhibitor for the photogenerated electrons and holes from Cu 2O, which collectively explained much enhanced stability and PEC activity of the Cu 2O/CuO composite. Thus, the electrochemical strategy proposed in this study for the synthesis of the Cu 2O/CuO composite opens a new way to use copper oxides as photocathode materials in PEC cells for a highly stable and effective water splitting. © 2012 The Royal Society of Chemistry.en
dc.description.sponsorshipThis work was supported by the KAUST Baseline Fund. We thank Drs Lan Zhao, Bei Zhang, and Mohamed Nejib Hedhili from King Abdullah University of Science and Technology (KAUST) for their help with SEM, XRD, and XPS, respectively. Z.Z is grateful for Sabic Postdoctoral Fellowship.en
dc.publisherRoyal Society of Chemistryen
dc.titleHighly stable copper oxide composite as an effective photocathode for water splitting via a facile electrochemical synthesis strategyen
dc.typeArticleen
dc.contributor.departmentWater Desalination and Reuse Research Center (WDRC)en
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.contributor.departmentEnvironmental Science and Engineering Programen
dc.contributor.departmentWater Desalination & Reuse Research Cntren
dc.contributor.departmentEnvironmental Nanotechnology Laben
dc.identifier.journalJournal of Materials Chemistryen
kaust.authorZhang, Zhonghaien
kaust.authorWang, Pengen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.