Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published February 2014 | Supplemental Material + Published
Journal Article Open

Photoelectrochemistry of core–shell tandem junction n–p^+-Si/n-WO_3 microwire array photoelectrodes

Abstract

Tandem junction (n–p^+-Si/ITO/WO_3/liquid) core–shell microwire devices for solar-driven water splitting have been designed, fabricated and investigated photoelectrochemically. The tandem devices exhibited open-circuit potentials of E_(∝) = −1.21 V versus E^0′(O_2/H_2O), demonstrating additive voltages across the individual junctions (n–p^+-Si E_(∝) = −0.5 V versus solution; WO_3/liquid E_(∝) = −0.73 V versus E^0′(O_2/H_2O)). Optical concentration (12×, AM1.5D) shifted the open-circuit potential to E_(∝) = −1.27 V versus E^0′(O_2/H_2O) and resulted in unassisted H_2 production during two-electrode measurements (anode: tandem device, cathode: Pt disc). The solar energy-conversion efficiencies were very low, 0.0068% and 0.0019% when the cathode compartment was saturated with Ar or H_2, respectively, due to the non-optimal photovoltage and band-gap of the WO_3 that was used in the demonstration system to obtain stability of all of the system components under common operating conditions while also insuring product separation for safety purposes.

Additional Information

© 2014 The Royal Society of Chemistry. Received 10 Sep 2013, Accepted 07 Nov 2013; First published online 16 Dec 2013. 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 Number DE-SC0004993. M.S. acknowledges the Resnick Sustainability Institute for a graduate fellowship. K.F. is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. S.A. acknowledges support from a U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under the EERE Fuel Cell Technologies Program. The authors would like to thank Dr Shu Hu for assistance in boron doping, Rick Gerhart for fabrication of the electrochemical cells used and Dr Andrew Leenheer for the WO3 refractive index data.

Attached Files

Published - c3ee43048k.pdf

Supplemental Material - c3ee43048k_si.pdf

Files

c3ee43048k_si.pdf
Files (8.1 MB)
Name Size Download all
md5:79d672758a4635d2dde2fe11b7be346c
7.6 MB Preview Download
md5:be1e0b6a6663601821514e5f86f7f99b
560.0 kB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 25, 2023