EXAFS study of Sn-doped hematite nanostructured films for water splitting

Hematite photoanodes are widely studied because they could offer low-cost and sustainable photoelectrodes for oxygen evolution reaction. Doping has been demonstrated an effective way to improve the photoelectrochemical properties. In particular, normally Sn is introduced into the hematite films deposited or grown on FTO (Fluorine-doped Tin Oxide) by high-temperature diffusion of Sn from the substrate. When used as photoanode, the photocurrent increases when the Sn doping iincreases from 0 to 3 at%, and then saturates (12% behaves as the 3%). Sn-doping sligtly modify the hematite lattice.We ask for a XAS investigation at Fe and Sn K-edge to measure the Fe and Sn site in hematite nanostructured films as a function of the Sn concentration and of the annealing temperature, with the aim to correlate the Sn site with the photoelectrochemical properties.