Novel application of photoelectron yield spectroscopy to the detection of hydrogen in steel under atmospheric conditions

抄録

The detection of hydrogen that permeates the steel specimen is crucial in the study of the mechanism of hydrogen embrittlement. However, the applicable analytical methods have been limited. In this study, we developed an experimental system of photoelectron yield spectroscopy (PYS) measurements to detect hydrogen in steel. The PYS measurement can evaluate the work function of a specimen under atmospheric conditions by detecting photoelectrons emitted from its surface. The measurement system was applied to monitor the work function of the nickel-plated surface on the hydrogen detection side of iron during a hydrogen permeation test. The initial value of the work function was 4.72 eV, indicating the presence of nickel hydroxide on the detection side. It was found that the work function of the detection side decreased by 0.35 eV after the introduction of hydrogen. In addition, the shape of the photoelectron yield spectrum changed, indicating a mixed phase of the nickel hydroxide and other substances with a smaller work function. It demonstrated that the PYS can detect the hydrogen at the specimen surface and can be a powerful tool in the study of hydrogen permeation.