Photoelectrochemical study of hydrogen in Zircalloy-2 oxide films

Photoelectrochemical study of hydrogen in oxide films of Zr based alloys for fuel cladding materials of light water reactors

“…These values were summarized in Table 2. This result shows that the all oxide films have an impurity levels in the original band gap because the value of 4.6-4.9 eV agrees well with previously reported band gap energy for ZrO 2 films, 4.8 eV [1,2,10,11]. It suggests that the sub-band was formed by doped elements or hydrogen or oxygen vacancy.…”

“…As shown in Fig. 2, the oxide film on hydride 1%NbZr and hydrided 2.5%NbZr possessed a peak around −0.53 and −0.56 V, respectively which suggests that some chemical reactions may occur around this potential only under the illumination in contrast with oxide film on hydrided Zr or Zircalloy without Nb [1,2]. That of hydrided Zry4-1.0Nb also possessed a peak around 0.2 V. However it appears independently of the illumination.…”

“…In the present study some hydrogen of hydrided samples was released during the oxidation but about 10,000 ppm (H/Zr ∼ = 0.01) hydrogen might retain in the oxide films. process of working electrodes and the experimental apparatus for PEC and EIS (electrochemical impedance spectroscopy) measurements have been described before [1,2]. The EIS measurements were performed in the frequency range from 1 × 10 6 to 1 × 10 −3 Hz with the ac amplitude of 100 mV.…”

“…Photoelectrochemical studies on the oxide films of Zr alloys have been performed and the effects of the hydrogen on the PEC properties of the oxide films have been investigated [1,2].…”