Facet Cutting and Hydrogenation of In2O3 Nanowires for Enhanced Photoelectrochemical Water Splitting
- 6 March 2014
- journal article
- research article
- Published by American Chemical Society (ACS) in ACS Applied Materials & Interfaces
- Vol. 6 (6), 4081-4088
- https://doi.org/10.1021/am4056358
Abstract
Semiconductor nanowires (NWs) are useful building blocks in optoelectronic, sensing, and energy devices and one-dimensional NWs have been used in photoelectrochemical (PEC) water splitting because of the enhanced light absorption and charge transport. It has been theoretically predicted that the {001} facets of body center cubic (bcc) In2O3 nanocrystals can effectively accumulate photogenerated holes under illumination, but it is unclear whether facet cutting of NWs can enhance the efficiency of PEC water splitting. In this work, the photocurrent of square In2O3 NWs with four {001} facets is observed to be an order of magnitude larger than that of cylindrical In2O3 NWs under the same conditions and subsequent hydrogen treatment further promotes the PEC water splitting performance of the NWs. The optimized hydrogenated In2O3 NWs yield a photocurrent density of 1.2 mA/cm2 at 0.22 V versus Ag/AgCl with a Faradaic efficiency of about 84.4%. The enhanced PEC properties can be attributed to the reduced band gap due to merging of the disordered layer-induced band tail states with the valence band as well as improved separation of the photogenerated electrons/holes between the In2O3 crystal core and disordered layer interface. The results provide experimental evidence of the important role of facet cutting, which is promising in the design and fabrication of NW-based photoelectric devices.Keywords
This publication has 49 references indexed in Scilit:
- Visible Light-Driven α-Fe2O3 Nanorod/Graphene/BiV1–xMoxO4 Core/Shell Heterojunction Array for Efficient Photoelectrochemical Water SplittingNano Letters, 2012
- Vertically Aligned Ta3N5 Nanorod Arrays for Solar‐Driven Photoelectrochemical Water SplittingAdvanced Materials, 2012
- Hematite/Si Nanowire Dual-Absorber System for Photoelectrochemical Water Splitting at Low Applied PotentialsJournal of the American Chemical Society, 2012
- Branched TiO2 Nanorods for Photoelectrochemical Hydrogen ProductionNano Letters, 2011
- Nanostructured WO3/BiVO4Heterojunction Films for Efficient Photoelectrochemical Water SplittingNano Letters, 2011
- Solar Water Splitting CellsChemical Reviews, 2010
- Nitrogen-Doped ZnO Nanowire Arrays for Photoelectrochemical Water SplittingNano Letters, 2009
- Mössbauer, NMR, Geometric, and Electronic Properties in S = 3/2 Iron PorphyrinsJournal of the American Chemical Society, 2009
- Photoelectrochemical cellsNature, 2001
- Visible-Light Photocatalysis in Nitrogen-Doped Titanium OxidesScience, 2001