Dissociating Water at n-Si Photoanodes Partially Covered with Fe Catalysts

Kiseok Oh (1, 2) , Vincent Dorcet (1) , Bruno Fabre (1, 2) , Gabriel Loget (1, 2)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 ScanMAT - Synthèse Caractérisation Analyse de la Matière

Stable, efficient, and low-cost photoanodes are urgently required for manufacturing water-splitting photoelectrochemical cells. Although silicon is a promising photoelectrode substrate, photocorrosion prevents its use in such devices, especially when employed as photoanodes for the oxygen evolution reaction (OER). Here, it is shown that Fe nanoparticles (NPs), deposited by cathodic electrodeposition onto n-Si, can promote hole transfer for the OER. The influence of the surface coverage, the Si structure, as well as the electrolyte are studied here in detail. It is reported that the NP density and the Si structuration drastically affect the photoelectrochemical performance and that the electrolyte influences the stability, allowing operation times as long as 130 h for these inhomogeneously coated photoelectrodes.

Keywords: silicon; iron; oxygen evolution reaction; photoelectrochemistry; Schottky junction; Photoelectrochemistry; Oxygen evolution reaction; Silicon; Iron

Domains: Chemical Sciences; Other

Kiseok Oh, Vincent Dorcet, Bruno Fabre, Gabriel Loget. Dissociating Water at n-Si Photoanodes Partially Covered with Fe Catalysts. Advanced Energy Materials, 2020, 10 (3), pp.1902963. ⟨10.1002/aenm.201902963⟩. ⟨hal-02438527⟩