Gallium Phosphide photoanode coated with TiO2 and CoOx for stable photoelectrochemical water oxidation

M. Alqahtani; S. Ben-Jabar; M. Ebaid; S. Sathasivam; P. Jurczak; X. Xia; A. Alromaeh; C. Blackman; Y. Qin; B. Zhang; B.S. Ooi; H. Liu; I.P. Parkin; J. Wu

doi:10.1364/OE.27.00A364

Gallium Phosphide photoanode coated with TiO2 and CoOx for stable photoelectrochemical water oxidation

M. Alqahtani, S. Ben-Jabar, M. Ebaid, S. Sathasivam, P. Jurczak, X. Xia, A. Alromaeh, C. Blackman, Y. Qin, B. Zhang, B.S. Ooi, H. Liu, I.P. Parkin, J. Wu

Chemical and Energy Engineering

Research output: Contribution to journal › Article › peer-review

20 Citations (Scopus)

2 Downloads (Pure)

Abstract

Gallium Phosphide (GaP) has a band gap of 2.26 eV and a valance band edge that is more negative than the water oxidation level. Hence, it may be a promising material for photoelectrochemical water splitting. However, one thing GaP has in common with other III-V semiconductors is that it corrodes in photoelectrochemical reactions. Cobalt oxide (CoOx) is a chemically stable and highly active oxygen evolution reaction co-catalyst. In this study, we protected a GaP photoanode by using a 20 nm TiO2 as a protection layer and a 2 nm cobalt oxide co-catalyst layer, which were both deposited
atomic layer deposition (ALD). A GaP photoanode that was modified by CoOx exhibited much higher photocurrent, potential, and photon-to-current efficiency than a bare GaP photoanode under AM1.5G illumination. A photoanode that was coated with both TiO2 and CoOx layers was stable for over 24 h during constant reaction in 1 M NaOH (pH 13.7) solution under one sun illumination.

Original language	English
Journal	Optics Express
Volume	27
Issue number	8
DOIs	https://doi.org/10.1364/OE.27.00A364
Publication status	Published - 18 Mar 2019

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1364/OE.27.00A364

oe-27-8-a364Final published version, 2.82 MBLicence: CC BY 4.0

Cite this

@article{d37fd38ca85e4c378fe642a7255d992b,

title = "Gallium Phosphide photoanode coated with TiO2 and CoOx for stable photoelectrochemical water oxidation",

abstract = "Gallium Phosphide (GaP) has a band gap of 2.26 eV and a valance band edge that is more negative than the water oxidation level. Hence, it may be a promising material for photoelectrochemical water splitting. However, one thing GaP has in common with other III-V semiconductors is that it corrodes in photoelectrochemical reactions. Cobalt oxide (CoOx) is a chemically stable and highly active oxygen evolution reaction co-catalyst. In this study, we protected a GaP photoanode by using a 20 nm TiO2 as a protection layer and a 2 nm cobalt oxide co-catalyst layer, which were both deposited atomic layer deposition (ALD). A GaP photoanode that was modified by CoOx exhibited much higher photocurrent, potential, and photon-to-current efficiency than a bare GaP photoanode under AM1.5G illumination. A photoanode that was coated with both TiO2 and CoOx layers was stable for over 24 h during constant reaction in 1 M NaOH (pH 13.7) solution under one sun illumination.",

author = "M. Alqahtani and S. Ben-Jabar and M. Ebaid and S. Sathasivam and P. Jurczak and X. Xia and A. Alromaeh and C. Blackman and Y. Qin and B. Zhang and B.S. Ooi and H. Liu and I.P. Parkin and J. Wu",

year = "2019",

month = mar,

day = "18",

doi = "10.1364/OE.27.00A364",

language = "English",

volume = "27",

number = "8",

}

TY - JOUR

T1 - Gallium Phosphide photoanode coated with TiO2 and CoOx for stable photoelectrochemical water oxidation

AU - Alqahtani, M.

AU - Ben-Jabar, S.

AU - Ebaid, M.

AU - Sathasivam, S.

AU - Jurczak, P.

AU - Xia, X.

AU - Alromaeh, A.

AU - Blackman, C.

AU - Qin, Y.

AU - Zhang, B.

AU - Ooi, B.S.

AU - Liu, H.

AU - Parkin, I.P.

AU - Wu, J.

PY - 2019/3/18

Y1 - 2019/3/18

N2 - Gallium Phosphide (GaP) has a band gap of 2.26 eV and a valance band edge that is more negative than the water oxidation level. Hence, it may be a promising material for photoelectrochemical water splitting. However, one thing GaP has in common with other III-V semiconductors is that it corrodes in photoelectrochemical reactions. Cobalt oxide (CoOx) is a chemically stable and highly active oxygen evolution reaction co-catalyst. In this study, we protected a GaP photoanode by using a 20 nm TiO2 as a protection layer and a 2 nm cobalt oxide co-catalyst layer, which were both deposited atomic layer deposition (ALD). A GaP photoanode that was modified by CoOx exhibited much higher photocurrent, potential, and photon-to-current efficiency than a bare GaP photoanode under AM1.5G illumination. A photoanode that was coated with both TiO2 and CoOx layers was stable for over 24 h during constant reaction in 1 M NaOH (pH 13.7) solution under one sun illumination.

AB - Gallium Phosphide (GaP) has a band gap of 2.26 eV and a valance band edge that is more negative than the water oxidation level. Hence, it may be a promising material for photoelectrochemical water splitting. However, one thing GaP has in common with other III-V semiconductors is that it corrodes in photoelectrochemical reactions. Cobalt oxide (CoOx) is a chemically stable and highly active oxygen evolution reaction co-catalyst. In this study, we protected a GaP photoanode by using a 20 nm TiO2 as a protection layer and a 2 nm cobalt oxide co-catalyst layer, which were both deposited atomic layer deposition (ALD). A GaP photoanode that was modified by CoOx exhibited much higher photocurrent, potential, and photon-to-current efficiency than a bare GaP photoanode under AM1.5G illumination. A photoanode that was coated with both TiO2 and CoOx layers was stable for over 24 h during constant reaction in 1 M NaOH (pH 13.7) solution under one sun illumination.

U2 - 10.1364/OE.27.00A364

DO - 10.1364/OE.27.00A364

M3 - Article

SN - 1094-4087

VL - 27

JO - Optics Express

JF - Optics Express

IS - 8

ER -