Light-driven water splitting is one of the most promising approaches for using solar energy in light of more sustainable development. In this paper, a highly efficient p-type copper(II) oxide photocathode is studied. The material, prepared by thermal treatment of CuI nanoparticles, is initially partially reduced upon working conditions and soon reaches a stable form. Upon visible-light illumination, the material yields a photocurrent of 1.3 mA cm-2 at a potential of 0.2 V vs a reversible hydrogen electrode at mild pH under illumination by AM 1.5 G and retains 30% of its photoactivity after 6 h. This represents an unprecedented result for a nonprotected Cu oxide photocathode at neutral pH. The photocurrent efficiency as a function of the applied potential was determined using scanning electrochemical microscopy. The material was characterized in terms of photoelectrochemical features; X-ray photoelectron spectroscopy, X-ray absorption near-edge structure, fixed-energy X-ray absorption voltammetry, and extended X-ray absorption fine structure analyses were carried out on pristine and used samples, which were used to explain the photoelectrochemical behavior. The optical features of the oxide are evidenced by direct reflectance spectroscopy and fluorescence spectroscopy, and Mott-Schottky analysis at different pH values explains the exceptional activity at neutral pH.

An Efficient CuxO Photocathode for Hydrogen Production at Neutral pH: New Insights from Combined Spectroscopy and Electrochemistry / T. Baran, S. Wojtyła, C. Lenardi, A. Vertova, P. Ghigna, E. Achilli, M. Fracchia, S. Rondinini, A. Minguzzi. - In: ACS APPLIED MATERIALS & INTERFACES. - ISSN 1944-8244. - 8:33(2016), pp. 21250-21260. [10.1021/acsami.6b03345]

An Efficient CuxO Photocathode for Hydrogen Production at Neutral pH: New Insights from Combined Spectroscopy and Electrochemistry

T. Baran
Primo
;
C. Lenardi;A. Vertova;S. Rondinini
Penultimo
;
A. Minguzzi
2016

Abstract

Light-driven water splitting is one of the most promising approaches for using solar energy in light of more sustainable development. In this paper, a highly efficient p-type copper(II) oxide photocathode is studied. The material, prepared by thermal treatment of CuI nanoparticles, is initially partially reduced upon working conditions and soon reaches a stable form. Upon visible-light illumination, the material yields a photocurrent of 1.3 mA cm-2 at a potential of 0.2 V vs a reversible hydrogen electrode at mild pH under illumination by AM 1.5 G and retains 30% of its photoactivity after 6 h. This represents an unprecedented result for a nonprotected Cu oxide photocathode at neutral pH. The photocurrent efficiency as a function of the applied potential was determined using scanning electrochemical microscopy. The material was characterized in terms of photoelectrochemical features; X-ray photoelectron spectroscopy, X-ray absorption near-edge structure, fixed-energy X-ray absorption voltammetry, and extended X-ray absorption fine structure analyses were carried out on pristine and used samples, which were used to explain the photoelectrochemical behavior. The optical features of the oxide are evidenced by direct reflectance spectroscopy and fluorescence spectroscopy, and Mott-Schottky analysis at different pH values explains the exceptional activity at neutral pH.
copper oxide; photocathode; hydrogen evolution reaction; photoelectrochemical water splitting; scanning electrochemical microscopy; XANES; EXAFS; XPS
Settore CHIM/02 - Chimica Fisica
   Low-cost photoelectrodes architectures based on the redox cascad principle for artificial photpsynthesis
   MINISTERO DELL'ISTRUZIONE E DEL MERITO
   RBFR13XLJ9_002
2016
Article (author)
File in questo prodotto:
File Dimensione Formato  
43_ACS_AMI_2016_Cu2O_Electrodes.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 5.57 MB
Formato Adobe PDF
5.57 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
ACS Applied Materials Interfaces_R3.docx

accesso aperto

Tipologia: Post-print, accepted manuscript ecc. (versione accettata dall'editore)
Dimensione 15.82 MB
Formato Microsoft Word XML
15.82 MB Microsoft Word XML Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/447882
Citazioni
  • ???jsp.display-item.citation.pmc??? 5
  • Scopus 40
  • ???jsp.display-item.citation.isi??? 38
social impact