The Effect of Gamma Irradiation on the Potential Behavior of Platinum and Stainless Steel Electrodes

Abstract

MECHANISM OF ANODE THERMAL REACTION AI~O~ -4-3C ~ 2AI -4-3C~O is --1.45 v at 971~ with the AI in the pure molten state, the carbon in the pure solid state, the Al~O~ dissolved in cryolite to give a 5 % solution by weight, and the compound CsO attached to the carbon anode surface. The free energy change for the reaction as written above is then 6 X 96,500 >< 1.45 AG~ = --n FE = = -4-200,609 cal 4.185 CO2 AG~ = --151,500 cal/g mole CO.~ CO AGf = --76,570 cal/g mole CO CsO AGf = --67,150 cal/g mole C~OThus it appears that the compound C~O is thermodynamically less stable than either CO or CO2, and its formation during electrolysis must be postulated to account for the observed reversible voltage and its decay with time on open circuit.

Electrochemical behaviour of gold and stainless steel under proton irradiation and active RedOx couples

“…For a given dose rate, the potential increase seems to be slightly dependent on the electrolyte solution. Similar behaviours of the free corrosion potentials have been obtained in Cl − solutions for AISI 304L [2], in groundwater (J-13) for AISI 304L and 316L [1] and in H 2 SO 4 for AISI 347L [4]. For noble metals, most studies reported in the literature deals with Pt [1,4,[6][7][8] for which the free exchange potential usually decreases under gamma irradiation.…”

“…One striking property for the interfaces irradiated in their pristine state is the reproducibility of the stages through which the interfaces go. It is interesting to compare this evolution to those reported in the literature for immersed electrodes under gamma irradiation [1][2][3][4][5][6][7][8][9][10]. Only one oxidising stage is generally observed where the free exchange potential reaches a quasi-steady value that varies is the range, +100 to +400 mV/SCE, depending on the nature of the stainless steels and solutions.…”

“…A literature review [1][2][3][4][5][6][7][8][9][10]12] shows that the present investigation provides the first data on the evolution of the free exchange potential of AISI 316L/Na 2 SO 4 (0.1 M) interfaces under 6 MeV proton irradiation for dose rates ranging from 8 × 10 6 to 4.8 × 10 7 Gy h −1 . The free exchange potential shows several stages of evolution depending on the dose accumulated by the AISI 316L/Na 2 SO 4 (0.1 M) interfaces.…”

“…Most of the in situ experiments on corrosion under irradiation that are reported in the literature concern the response of electrodes immersed in electrochemical cells irradiated by gamma [1][2][3][4][5][6][7][8]. The gamma sources that are generally used are 60 Co and the dose rates vary typically in the range 10 3 < dr(Gy h −1 ) < 10 4 .…”

“…The gamma sources that are generally used are 60 Co and the dose rates vary typically in the range 10 3 < dr(Gy h −1 ) < 10 4 . A number of authors report that gamma irradiation shifts the free exchange potential of stainless steels (AISI 304L, AISI 316L and AISI 347) in the anodic direction [1][2][3][4][5]. The free corrosion potential is reported to reach a quasi-steady state in most cases.…”