TY - JOUR
T1 - Temperature dependence of the D-H replacement rates in D-implanted oxide ceramics exposed to H2O vapor
AU - Morita, K.
AU - Tsuchiya, B.
AU - Nagata, S.
AU - Katahira, K.
AU - Yoshino, M.
AU - Arita, Y.
AU - Ishijima, T.
AU - Sugai, H.
N1 - Funding Information:
This study was supported by Industrial Technology Research Grant Program in 05A0002c from New Energy Development Organization (NEDO) of Japan and also partly supported by Feasibility Study of Japan Science and Technology (JST), Tokai Plaza. The authors are grateful for valuable co-operation to the members of the Tandem accelerator group in Advanced Research Center of Metallic Glasses, Institute of Materials Research, Tohoku University.
PY - 2007/5
Y1 - 2007/5
N2 - Temperature dependence of the D-H replacement rates in D-implanted BaCe0.9Y0.1O3-δ exposed to H2O vapor has been studied by means of the ERD technique with MeV He+ ion beam. It is found that the decay constant of D, namely D-H replacement rate increases monotonically as the specimen temperature is elevated from the implantation (room) temperature up to 50 °C. The concentration of H absorbed in the specimen by the D-H replacement is also found to be almost comparable to the implantation concentration of D, while the concentration of D implanted and H absorbed by the D-H replacement are reduced when the specimen is annealed in the vacuum. The apparent activation energy for the decay constant of D at elevated temperatures is found to be 0.70 eV, which is considerably higher than the one which is expected to be obtained at cooling temperatures below the implantation temperature. No reduction in the concentration of H absorbed by the D-H replacement is ascribed to enough fast absorption of H due to splitting of H2O at the surface, in comparison with thermal release of D and H. The higher activation energy for the decay constant of D is also ascribed to the contribution of thermal detrapping to emission of D2 and HD due to the local molecular recombination of D and H detrapped thermally with D and H in traps.
AB - Temperature dependence of the D-H replacement rates in D-implanted BaCe0.9Y0.1O3-δ exposed to H2O vapor has been studied by means of the ERD technique with MeV He+ ion beam. It is found that the decay constant of D, namely D-H replacement rate increases monotonically as the specimen temperature is elevated from the implantation (room) temperature up to 50 °C. The concentration of H absorbed in the specimen by the D-H replacement is also found to be almost comparable to the implantation concentration of D, while the concentration of D implanted and H absorbed by the D-H replacement are reduced when the specimen is annealed in the vacuum. The apparent activation energy for the decay constant of D at elevated temperatures is found to be 0.70 eV, which is considerably higher than the one which is expected to be obtained at cooling temperatures below the implantation temperature. No reduction in the concentration of H absorbed by the D-H replacement is ascribed to enough fast absorption of H due to splitting of H2O at the surface, in comparison with thermal release of D and H. The higher activation energy for the decay constant of D is also ascribed to the contribution of thermal detrapping to emission of D2 and HD due to the local molecular recombination of D and H detrapped thermally with D and H in traps.
KW - Hydrogen isotope exchange
KW - Hydrogen production
KW - Ion beam analysis
KW - Oxide ceramics
KW - Water splitting
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U2 - 10.1016/j.nimb.2006.12.105
DO - 10.1016/j.nimb.2006.12.105
M3 - Article
AN - SCOPUS:34147155840
VL - 258
SP - 282
EP - 286
JO - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
JF - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
SN - 0168-583X
IS - 1
ER -
