Abstract
A new strategy for surface treatment of hematite nanoplates for efficient photoelectrochemical (PEC) performances is proposed. Silver orthophosphate (Ag3PO4) has been adopted to mediate the formation of α-Fe2O3 films. Phosphate ions in Ag3PO4 is found to cause a significant morphology change during annealing process, from β-FeOOH nanorod arrays to hematite nanoplates. Meanwhile, Ag ions is doped into α-Fe2O3 film. The obtained nanoplate structured Fe2O3–Ag–P films demonstrate much higher photoelectrochemical performance as photoanodes than the bare Fe2O3 nanorod thin films. The effects of phosphate and silver ions on the morphology, surface characteristics and the PEC properties of the photoanodes are investigated.
Highlights
IntroductionHematite (α-Fe2O3) has been considered as an attractive semiconductor material for photoelectrochemical (PEC) water splitting due to its narrow band gap (2.1–2.2 eV),
Hematite (α-Fe2O3) has been considered as an attractive semiconductor material for photoelectrochemical (PEC) water splitting due to its narrow band gap (2.1–2.2 eV), appropriate chemical stability in alkaline environment, nontoxicity, and low cost [1,2,3,4]
These results demonstrate that the in-situ formed Ag3PO4 in soaking solution is more efficient for enhancement in photocurrent than previous spin-coated Ag3PO4 powder
Summary
Hematite (α-Fe2O3) has been considered as an attractive semiconductor material for photoelectrochemical (PEC) water splitting due to its narrow band gap (2.1–2.2 eV),. The inherent obstacles for hematite as photoanode in PEC performances are mainly concerned with the extremely short hole diffusion length (2–4 nm) [7], poor conductivity[8] and slow oxygen evolution reaction kinetics[9] These features limit charge transport and cause a serious recombination of electrons and holes. A thin overlayer of NixFe2-xO3 on the surface of hematite nanotubes was found to have accelerated surface oxygen evolution, promoted charge transfer, and resulted in better performances in water splitting relative to the pristine α-Fe2O3[28]. Photoelectrochemical measurements were performed using a three-electrode configuration in 1.0 M NaOH (pH 13.6) aqueous solution at a potentiostat (AutoLab-30 potentiostat), with the hematite samples as the working photoanodes, Ag/AgCl(saturated KCl) as the reference electrode, and Pt as the counter electrode. All potentials were converted to the reversible hydrogen electrode (RHE) scale using the equation VRHE= VAg/AgCl + 0.1976 V + pH (0.059 V)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
