Facile fabrication of tin-doped hematite photoelectrodes - effect of doping on magnetic properties and performance for light-induced water splitting

0387442 - ÚFM 2013 RIV GB eng J - Journal Article
Frydrych, J. - Machala, L. - Tuček, J. - Šišková, K. - Filip, J. - Pechoušek, J. - Šafářová, K. - Vondráček, Martin - Seo, J. H. - Schneeweiss, Oldřich - Grätzel, M. - Sivula, K. - Zbořil, R.
Facile fabrication of tin-doped hematite photoelectrodes - effect of doping on magnetic properties and performance for light-induced water splitting.
Journal of Materials Chemistry. Roč. 22, č. 43 (2012), s. 23232-23239. ISSN 0959-9428
R&D Projects: GA ČR GA106/08/1440; GA MŠMT(CZ) LC06058
Institutional support: RVO:68081723 ; RVO:68378271
Keywords : Alpha-Fe203 thin-films * photoanodes * electrodes * nanostructures * oxides
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 6.108, year: 2012

We present a new, easily scalable method for the deposition of nanocrystalline hematite photoelectrodes based on the spin-coating of a mixed solution containing tin(II) and iron(III) chlorides followed by thermal treatment. Our facile approach does not require any additional film-forming organic species and allows simple control of the photoelectrochemical performance of the electrode by adjusting the degree of tin doping. When annealed at 650 degrees C a strong increase in the water oxidation photocurrent is observed with increasing tin concentration. The maximum performance (0.45 mA cm(-2) at 1.43 V vs. RHE) was found at the highest possible tin loading (20 : 100, Sn : Fe). The contrasting performance of electrodes annealed at 650 degrees C and 800 degrees C suggests different activation processes for dopant diffusion and activation. The doping of tin into the crystal structure of hematite thin films is directly evidenced by X-ray photoelectron spectroscopy and indirectly by changes in the intrinsic magnetic parameters (Morin temperature, Neel temperature) of the hematite films. The magnetization measurements thus represent a potential technique to quantify doping amounts in hematite.
Permanent Link: http://hdl.handle.net/11104/0216571