An electrochemical deposition route for obtaining α-Fe2O3 thin films -: II.: EQCM study and semiconductor properties

The electrochemical formation of hematite (alpha-Fe2O3) precursor thin films (oxyhydroxide iron compounds), onto gold substrates in an aqueous solution of Fe (III) + KF + H2O2 was investigated in situ using an electrochemical quartz crystal microbalance (EQCM) and voltammetric techniques. Nanostructured alpha-Fe2O3 obtained after annealing of oxyhydroxide iron compounds thin films have been prepared onto SnO2/F covered glass substrates through a potential cycling procedure in this electrolytic bath. Photoelectrochemical measurements, carried out in 0.1 M NaOH + 0.05 M KI electrolyte at pH 13, show an n-type behavior, a flatband potential of -1.08 V vs saturated mercury/mercury sulfate reference electrode, and an apparent donor density of 1.26 X 10(19) cm(-3) at 1 kHz. (C) 2007 The Electrochemical Society.