Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4
In this paper, the synergistic effect of porosity and gradient of Mo doping in BiVO4 photoanodes for improving charge separation and solar water oxidation performance is reported. A simple solution-based, three-step fabrication route was adopted using a layer-by-layer assembling technique. A water o...
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sg-ntu-dr.10356-804202023-07-14T15:50:05Z Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 Antony, Rajini P. Zhang, Mengyuan Zhou, Kaiqi Barber, James Wong, Lydia Helena Loo, Joachim Say Chye School of Materials Science & Engineering Engineering::Materials Porosity Solar Water Oxidation In this paper, the synergistic effect of porosity and gradient of Mo doping in BiVO4 photoanodes for improving charge separation and solar water oxidation performance is reported. A simple solution-based, three-step fabrication route was adopted using a layer-by-layer assembling technique. A water oxidation photocurrent of ∼1.73 mA cm–2 at 1.23 V vs reversible hydrogen electrode in neutral pH was achieved without using any sacrificial agent or electrocatalyst. The gradient Mo doping was found to enhance charge separation efficiency, which was verified through a shift in the water oxidation onset potential cathodically to ∼200 mV. In addition, these results were further confirmed by a higher open-circuit photovoltage and flat band potential investigations. This was attributed to the surface energetics played by gradient Mo doping that served as the driving force in reducing the onset potential for water oxidation. The coupled effect of enhanced light absorption and charge separation was revealed by monitoring the difference in decoupling the water oxidation efficiencies of porous and planar Mo:BiVO4 photoanodes. This study demonstrated an improvement in the catalytic and charge separation efficiency of Mo:BiVO4 photoanodes due to the introduction of porous structured homojunctions in a gradient manner. The simple synthesis approach adopted in the present study can be utilized and scaled up in making efficient photoanodes for competent solar water oxidation cells. Published version 2019-11-07T05:31:03Z 2019-12-06T13:49:02Z 2019-11-07T05:31:03Z 2019-12-06T13:49:02Z 2018 Journal Article Antony, R. P., Zhang, M., Zhou, K., Loo, J. S. C., Barber, J., & Wong, L. H. (2018). Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4. ACS Omega, 3(3), 2724-2734. doi:10.1021/acsomega.7b01794 https://hdl.handle.net/10356/80420 http://hdl.handle.net/10220/50367 10.1021/acsomega.7b01794 en ACS Omega © 2018 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. 11 p. application/pdf |
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Engineering::Materials Porosity Solar Water Oxidation Antony, Rajini P. Zhang, Mengyuan Zhou, Kaiqi Barber, James Wong, Lydia Helena Loo, Joachim Say Chye Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
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In this paper, the synergistic effect of porosity and gradient of Mo doping in BiVO4 photoanodes for improving charge separation and solar water oxidation performance is reported. A simple solution-based, three-step fabrication route was adopted using a layer-by-layer assembling technique. A water oxidation photocurrent of ∼1.73 mA cm–2 at 1.23 V vs reversible hydrogen electrode in neutral pH was achieved without using any sacrificial agent or electrocatalyst. The gradient Mo doping was found to enhance charge separation efficiency, which was verified through a shift in the water oxidation onset potential cathodically to ∼200 mV. In addition, these results were further confirmed by a higher open-circuit photovoltage and flat band potential investigations. This was attributed to the surface energetics played by gradient Mo doping that served as the driving force in reducing the onset potential for water oxidation. The coupled effect of enhanced light absorption and charge separation was revealed by monitoring the difference in decoupling the water oxidation efficiencies of porous and planar Mo:BiVO4 photoanodes. This study demonstrated an improvement in the catalytic and charge separation efficiency of Mo:BiVO4 photoanodes due to the introduction of porous structured homojunctions in a gradient manner. The simple synthesis approach adopted in the present study can be utilized and scaled up in making efficient photoanodes for competent solar water oxidation cells. |
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School of Materials Science & Engineering |
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School of Materials Science & Engineering Antony, Rajini P. Zhang, Mengyuan Zhou, Kaiqi Barber, James Wong, Lydia Helena Loo, Joachim Say Chye |
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Article |
author |
Antony, Rajini P. Zhang, Mengyuan Zhou, Kaiqi Barber, James Wong, Lydia Helena Loo, Joachim Say Chye |
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Antony, Rajini P. |
title |
Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
title_short |
Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
title_full |
Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
title_fullStr |
Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
title_full_unstemmed |
Synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient Mo:BIVO4 |
title_sort |
synergistic effect of porosity and gradient doping in efficient solar water oxidation of catalyst-free gradient mo:bivo4 |
publishDate |
2019 |
url |
https://hdl.handle.net/10356/80420 http://hdl.handle.net/10220/50367 |
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1772827377941872640 |