The hydrogen produced by the artificial photosynthesis, that is to say, dissociation of the water from the solar energy is an alternative production and promising energy storage compared to the use of fossil fuels and the growing use of batteries with significant impacts on the environment.
Effective dissociation of water by a semiconductor can be achieved with a bandgap suitable for the absorption of most of the solar spectrum. But this photoelectrode must also remain stable in highly alkaline or acidic electrolytes.
In this work published by the prestigious Royal Society of Chemistry, the authors of FOTON Institute and University College London present for the first time a perfectly relaxed monocrystalline alloy, GaP0.67Sb0.33, deposited on the substrate. Low cost of silicon with a direct bandgap set at 1.65 eV by molecular beam epitaxy (MBE) with no sign of chemical disorder.
Under solar illumination, the photoanode produces an incident current photon efficiency (IPCE) of 67.1% over the visible range between wavelengths between 400 and 650 nm.
In addition, the photo-anode GaP0.67Sb0.33 remains stable for 5 hours without degradation of the photocurrent under strongly alkaline conditions under illumination.
This demonstration paves the way for an almost ideal photoelectrochemical system in tandem configuration with a theoretical yield of 27% between solar energy and hydrogen.
Photoelectrochemical water oxidation of GaP (1-x) Sb x with a direct bandgap of 1.65 eV for full-spectrum solar energy harvesting.
Hydrogen produced by artificial photosynthesis, that is, dissociation of water from solar energy is a promising energy production and storage alternative to the use of fossil fuels and the growing use of batteries with significant impacts on the environment. Effective dissociation of water by a semiconductor can be achieved with a bandgap suitable for the absorption of most of the solar spectrum. But this photoelectrode must also remain stable in highly alkaline or acidic electrolytes. In this work published by the prestigious RSC, the authors of Institut Foton and University College London present for the first time a perfectly relaxed monocrystalline alloy, GaP 0.67 Sb 0.33 , deposited on the low-cost silicon substrate with a direct bandgap set at 1.65 eV by molecular beam epitaxy ( MBE ) without sign of chemical disorder. Under solar illumination, the photoanode produces an incident current photon efficiency ( IPCE ) of 67.1% over the visible range between wavelengths between 400 and 650 nm. In addition, the photo-anode GaP 0.67 Sb 0.33remains stable for 5 hours without photocurrent degradation under strongly alkaline conditions under illumination. This demonstration paves the way for an almost ideal photoelectrochemical system in tandem configuration with a theoretical yield of 27% between solar energy and hydrogen.
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