Synthesis and hydrogen-evolution activity of tungsten selenide thin films deposited on tungsten foils
Abstract
Thin films of WSe_2 have been deposited onto a conductive substrate (tungsten foil) using a relatively simple chemical-vapor-transport technique. X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy indicated that the films consisted of micron-sized single crystals of WSe_2 that were oriented perpendicular to the surface of the tungsten foil substrate. Linear sweep voltammetry was used to assess the ability of the WSe_2 films to catalyze the hydrogen-evolution reaction and chronopotentiometry was used to gauge the temporal stability of the catalytic performance of the films under cathodic conditions. A 350 mV overpotential (η) was required to drive the hydrogen-evolution reaction at a current density of −10 mA cm^(−2) in aqueous 0.5 M H_2SO_4, representing a significant improvement in catalytic performance relative to the behavior of macroscopic WSe_2 single crystals. The WSe_2 thin films were relatively stable under catalytic conditions, with the overpotential changing by only ∼10 mV after one hour and exhibiting an additional change of ∼5mV after another hour of operation.
Additional Information
© 2014 Elsevier B.V. Available online 11 December 2013; Special Issue in Honour of Kingo Itaya. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. We also acknowledge the MPR Institute for helpful discussions and assistance in the preparation of this manuscript.Attached Files
Supplemental Material - Figs._S1-S5.docx
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Additional details
- Eprint ID
- 43454
- Resolver ID
- CaltechAUTHORS:20140121-113850320
- Department of Energy (DOE)
- DE-SC0004993
- Created
-
2014-01-21Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Caltech groups
- JCAP