Abstract

The semiconducting properties of sputtered magnetite and oxidized magnetite layers with different Fe(II) contents were compared with the passive film on iron. Electrochemical impedance spectroscopy and photoelectrochemical experiments were carried out in borate buffer, pH 8.4. An evaluation of the impedance data according to the Mott‐Schottky concept showed that the capacitance of all films is linked with their doping concentrations rather than their thicknesses and that the doping species of the passive film on iron is Fe(II). For the passive film a potential‐dependent doping concentration was found. Photoelectrochemical investigation of the passive film and the sputtered oxide layers showed that for low doping concentrations, the photocurrent increases with doping, whereas for high doping concentrations, an increase in doping leads to a decrease of the photocurrent. Possible causes for this effect are discussed. Further, the combination of a light reflectance technique with photocurrent measurements allowed consideration of light absorption effects in the data treatment and separation of photocurrent contributions from the space‐charge layer from film‐thickness effects.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.