Three-step pulse electrochemical deposition of FeSxOy thin films and their characterization

Abstract

Three-step pulse electrochemical deposition was used to deposit FeSxOy thin films on indium-tinoxide-coated glass substrates at room temperature from solution containing Na2S2O3 and FeSO4. The deposition was conducted under two different potential shifts direction (condition A: from negative to positive and condition B: from positive to negative) with intermediate potential V2 variation. All the deposited films were amorphous. In Raman measurements, peaks attributed to marcasite and Fe1+xS were observed. The O/Fe ratio is larger than unity. The films deposited under condition A with an intermediate potential V2 = 0.6 V and condition B with V2 = 0.4 V showed a band gap which is estimated around 2.3-2.45 eV, larger than literature value of Fe2O3 (2.1 eV). In the photoelectrochemical measurement, nearly intrinsic behavior was confirmed.