Photoelectrochemical water splitting using strain-balanced multiple quantum well photovoltaic cells. Issue 10 (20th August 2019)

• Record Type: Journal Article
• Authors: Steiner, Myles A.; Barraugh, Collin D.; Aldridge, Chase W.; Alvarez, Isabel Barraza; Friedman, Daniel J.; Ekins-Daukes, Nicholas J.; Deutsch, Todd G.; Young, James L.
• Is Part Of: Sustainable energy & fuels. Volume 3:Issue 10(2019)
• Page Start: 2837
• Page End: 2844
• Publication Date: 2019-08-20
• Subjects: Renewable energy sources -- Periodicals; Fuel cells -- Periodicals; Electric batteries -- Periodicals; Electrochemistry -- Periodicals; 660.297
• DOI: 10.1039/c9se00276f
• Languages: English
• ISSNs: 2398-4902

Abstract

Abstract : Strain-balanced GaInAs/GaAsP quantum wells were incorporated into the classical GaInP/GaAs tandem photoelectrochemical water splitting device to increase the range of photon absorption and achieve higher solar-to-hydrogen efficiencies. Abstract : Starting from the classical GaInP/GaAs tandem photoelectrochemical water splitting device, higher solar-to-hydrogen efficiencies can be pursued by extending photon absorption to longer wavelengths. We incorporate strain-balanced GaInAs/GaAsP quantum wells into the bottom GaAs junction, to increase the range of photon absorption. The inclusion of 1.34 eV quantum wells in the depletion region of the bottom cell extends the absorption edge to 930 nm. With a corresponding increase in the thickness of the top cell for current matching, the light-limiting photocurrent increases by >8%. The estimated solar-to-hydrogen efficiency is 13.6 ± 0.5%, and we show a pathway to further improvement. With the semiconductor device remaining on the growth substrate, this quantum well architecture may enable improved stability and durability of the photoelectrochemical electrodes.