2020, Stepanov, V. A., Alekseevich, C. V., Grigorievich, P. Y., Petrovich, L. V., Степанов, Владимир Александрович

© 2020 Obninsk Institute for Nuclear Power Engineering, National Research Nuclear University 'MEPhI'. All rights reserved.In asymmetric supercapacitors, electric charges are separated and accumulated during neutron irradiation. The paper deals with current sources with radioactive isotopes (CSRI) based on 100 F supercapacitors made by means of neutron activation of elements introduced into the electrodes of substances (BN or SrO). After neutron irradiation with a dose of up to 400 Gy, the supercapacitors turn into CSRI with a charging rate of up to 7.8 μV/day. The CSRI charging rate increases in proportion to the activation neutron dose up to 14 kGy. This is due to the production of β-active isotopes as a result of the reactions 14N(n, p)14C and 88Sr(n, γ)89Sr in the supercapacitor electrodes. An estimate of the radiation-induced charge accumulation rate, taking into account the energy released during β-decay of 14C and 89Sr, excludes the known charge separation mechanisms in a condensed medium due to the ionization and production of secondary electrons, electron-hole pair generation, etc. The electric charge separation and accumulation in CSRI occurs as a result of nonequilibrium thermoelectric phenomena in the near-electrode nano-regions. Nuclear reactions in nanoscale regions produce «temperature gradients» up to 105 K/nm. This leads to the «evaporation» of up to 1013 electrons from nanocrystallites at times of ~ 10-11 s.