Anodic Photocurrents and Corrosion Currents on Passive and Active-Passive Metals
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چکیده
A photoelectrochemical study was made to compare Zr, Ti, Zn, Sn, Fe, and Cu in 1 N sulfuric acid and/or 1 N KOH. This group includes spontaneously passive, active-passive, and nonpassive metals. The apparent direct and indirect bandgaps and the flatband potentials were measured for the anodic oxides of each metal. (The bandgaps and flat-band potentials can be used to identify the anodic oXide.) The corrosion currents and the photocurrents were compared. The photocurrent was generated by pulses of monochromatic light. Relationships are observed between the corrosion current and the photocurrent, notably for the formation of new oxides and the active-passive transition.
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