fulltext.study @t Gmail

Enhancing the photoelectrochemical performance of hematite (α-Fe2O3) electrodes by cadmium incorporation

Paper ID Volume ID Publish Year Pages File Format Full-Text
46591 46442 2011 9 PDF Available
Title
Enhancing the photoelectrochemical performance of hematite (α-Fe2O3) electrodes by cadmium incorporation
Abstract

Photoelectrochemical (PEC) water oxidation using hematite (α-Fe2O3) is of great interest in terms of solar fuels and artificial photosynthesis. In this study, Cd-incorporated nanocrystalline hematite films (Cd–Fe2O3) supported on conducting glass have been prepared via co-electrodeposition of aqueous Fe(III) and Cd(II) with varying Cd:Fe atomic ratios (up to 3.2 at.%) and optimized for their PEC performances under a simulated solar light (AM 1.5-irradiation). Surface analysis indicates that the Cd co-deposition increases the hematite particle size from ca. 50 nm to 70–100 nm due to interparticle agglomeration and decreases the overall UV–Vis absorbance of hematite. X-ray photoelectron spectroscopic study also indicates that Cd incorporation shifts the binding energy of oxygen atoms to lower energy direction whereas it does not affect the binding energy of Fe 3d. This suggests that Cd exists mainly as CdO and/or Cd(OH)2 in the hematite surface. When an optimal level of Cd content (∼1 at.%) is electrodeposited, the photocurrent of hematite film is significantly enhanced by a factor of ca. four at E = 1.23 VRHE under AM 1.5-irradiation and the photoactive spectral region is red-shifted. Electrochemical impedance spectroscopic analysis further reveals that the flat band potential of hematite is shifted by ca. −30 mV to negative potential direction and the charge transfer resistance (Rct) is significantly reduced by Cd incorporation. Detailed surface analyses, optimization for preparation condition of hematite films, and discussion for PEC behaviors were described.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The photocurrent of hematite film is four-fold enhanced by Cd doping at 1%. ► Cd exists mainly as CdO and/or Cd(OH)2 in the hematite surface. ► The photoactive spectral region is red-shifted by Cd doping. ► The primary role of Cd is to increase the electrical conductivity of hematite.

Keywords
Electrodeposition; Semiconductor; Water oxidation; Conductivity; Doping
First Page Preview
Enhancing the photoelectrochemical performance of hematite (α-Fe2O3) electrodes by cadmium incorporation
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis B: Environmental - Volume 110, 2 November 2011, Pages 207–215
Authors
, , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us