Understanding the synergistic between optimum dopant loading and charge transfer kinetics in platinum-mediated nanostructured hematite thin films

Y. W. Phuan, M. N. Chong, K. Egamparan, B. K. Lee, T. Zhu, E. S. Chan

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15 Citations (Scopus)

Abstract

Photoelectrochemical (PEC) water splitting process has received immense attention owing to its ability in sustainably producing solar hydrogen from water. The main aim of this study was to systematically optimise the Platinum (Pt) dopant loadings and understand its synergistic role in enhancing the photoactivity in nanostructured hematite (α-Fe2O3) thin films. Through the optimisation study, it was found the 3�mol% Pt-doped nanostructured hematite thin film exhibited the highest photocurrent density of 0.91�mA/cm2 at 0.7�V vs Ag/AgCl in 1�M NaOH. In comparison with the bare hematite film, this was a 3-fold enhancement in terms of measured photocurrent density. Such an enhancement in the measured photocurrent density was attributed to the increased donor density caused due to the incorporation of optimum Pt dopant. Further EIS analysis revealed that the flat-band potential of hematite was shifted to a more negative potential by 30�mV while the charge transfer resistance was considerably reduced through the incorporation of Pt dopant. All these suggested that the successful doping of optimum Pt loading will lead to a visible active, lower charge transfer resistance and an enhanced separation efficiency of the photogenerated charge carriers in nanostructured hematite thin films.

Original languageEnglish
Pages (from-to)249-257
Number of pages9
JournalJournal of the Taiwan Institute of Chemical Engineers
Volume66
DOIs
Publication statusPublished - 1 Sept 2016

Keywords

  • Doping
  • Electrodeposition
  • Hematite
  • Nanostructured
  • Photoelectrochemical
  • Water Splitting

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