Vapor phase processing of α-Fe2O3 photoelectrodes for water splitting: An insight into the structure/property interplay
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Details
Original language | English |
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Pages (from-to) | 8667-8676 |
Number of pages | 10 |
Journal | ACS Applied Materials and Interfaces |
Volume | 7 |
Issue number | 16 |
Early online date | 15 Apr 2015 |
DOIs | |
Publication status | Published - 2015 |
Publication type | A1 Journal article-refereed |
Abstract
Harvesting radiant energy to trigger water photoelectrolysis and produce clean hydrogen is receiving increasing attention in the search of alternative energy resources. In this regard, hematite (alpha-Fe2O3) nanostructures with controlled nano-organization have been fabricated and investigated for use as anodes in photoelectrochemical (PEC) cells. The target systems have been grown on conductive substrates by plasma enhanced-chemical vapor deposition (PE-CVD) and subjected to eventual ex situ annealing in air to further tailor their structure and properties. A detailed multitechnique approach has enabled to elucidate between system characteristics and the generated photocurrent. The present alpha-Fe2O3 systems are characterized by a high purity and hierarchical morphologies consisting of nanopyramids/organized dendrites, offering a high contact area with the electrolyte. PEC data reveal a dramatic response enhancement upon thermal treatment, related to a more efficient electron transfer. The reasons underlying such a phenomenon are elucidated and discussed by transient absorption spectroscopy (TAS) studies of photogenerated charge carrier kinetics, investigated on different time scales for the first time on PE-CVD Fe2O3 nanostructures.
ASJC Scopus subject areas
Keywords
- hematite, hierarchical structures, PE-CVD, PEC, transient absorption spectroscopy, water splitting