In spite of the obvious importance of interfacial radiation chemistry, surprisingly, little is known about underlying mechanisms.To describe the radiation chemistry at an interface it is necessary to have information about: the homogeneous radiation chemistry of the two phases in contact the energy deposition in the system the yield of radiolysis products and the reactivity of radiolysis products at the interface between the two homogeneous phases. In nuclear technology, interfaces exposed to ionizing radiation constitute a key-point in any safety assessment and a common theme is the impact of radiation-induced corrosion in nuclear power plants, nuclear fuel reprocessing plants and repositories for radioactive waste 16, 17. In fact, one of the most crucial and thereby also interesting components of a system from a performance perspective is the interface between two phases.
However, most systems of practical relevance are not homogeneous. The consequences of the exposure of many homogeneous systems to ionizing radiation are well-known on the basis of both experimental and theoretical studies performed over a period close to a century 15. Because of this it is of vital importance to elucidate the effects of ionizing radiation on copper and on the interface between copper and surrounding matter. A rather unique feature of the copper used in spent nuclear fuel canisters is that it will be exposed to ionizing radiation 10, 11, 12, 13, 14. As for the other barrier materials, studies of processes that have potential impact on the long-term integrity of the copper layer have been conducted both in laboratories and in the field under repository conditions 9. In some repository concepts, metallic copper has been proposed as an outer corrosion resistant barrier on canisters containing the spent nuclear fuel 6, 7, 8.
#Radiation island crystal converter location series#
The safety relies on a series of natural and engineered barriers preventing the highly radioactive material from migrating into the biosphere 5. The safety of such repositories must be guaranteed for time periods longer than the history of homo sapiens 4. However, at present, one of the most difficult issues to tackle is the long-term safety of repositories for radioactive waste originating from nuclear power plants, in particular the spent nuclear fuel 3. The safety of operating nuclear power plants is usually of main concern in discussions comparing different energy production techniques. Nuclear power is often argued to be a fossil-free alternative in the global spectrum of electricity generation 1, 2. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H 2(g) at a pressure of 1 atm in a non-irradiated dry system. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste.
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