TY - JOUR
T1 - Mixed mechanisms controlling hydrogen-metal reactions under steady state conditions
T2 - the diffusion-interface mechanism
AU - Mintz, Moshe H.
N1 - Funding Information:
This work was partiallys upportedby a joint grant of the Israel Council of Higher Educationa nd the Israel Atomic AgencyC ommissionT. hanksa re due to Mr. Y. Levitin for his assistancein the computatioonf the curves demonstrateind this paper.
PY - 1991/10/21
Y1 - 1991/10/21
N2 - Hydrogen-metal reactions (forming metal hydrides) which progress by a "contractingenvelope" morphology under steady state conditions (i.e. at a constant velocity of the reaction front) may be controlled by different rate-limiting steps. Usually, a single-step mechanism (e.g. diffusion, interface processes, etc.) is considered for the interpretation of experimental kinetic data. In the present work a more generalized mixed mechanism which involves simultaneous contributions of two microscopic processes (i.e. diffusion and interface emission) is treated. The single-step mechanisms are derived as particular extreme cases of the generalized formalism. The requirements which establish the existence of either a single or a mixed mechanism are evaluated and the experimental kinetic behaviour is discussed.
AB - Hydrogen-metal reactions (forming metal hydrides) which progress by a "contractingenvelope" morphology under steady state conditions (i.e. at a constant velocity of the reaction front) may be controlled by different rate-limiting steps. Usually, a single-step mechanism (e.g. diffusion, interface processes, etc.) is considered for the interpretation of experimental kinetic data. In the present work a more generalized mixed mechanism which involves simultaneous contributions of two microscopic processes (i.e. diffusion and interface emission) is treated. The single-step mechanisms are derived as particular extreme cases of the generalized formalism. The requirements which establish the existence of either a single or a mixed mechanism are evaluated and the experimental kinetic behaviour is discussed.
UR - http://www.scopus.com/inward/record.url?scp=0026244143&partnerID=8YFLogxK
U2 - 10.1016/0925-8388(91)90012-K
DO - 10.1016/0925-8388(91)90012-K
M3 - Article
AN - SCOPUS:0026244143
SN - 0925-8388
VL - 176
SP - 77
EP - 87
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
IS - 1
ER -