Simulating a Cell Based on a Three-Dimensional Heterojunction with Distributed Charge-Carrier Generation

Abstract

The idea of designing solar cells with a distributed heterojunction consists in spreading the donor–acceptor interface to the entire active-layer volume in order to enhance the efficiency of the dissociation of photogenerated excitons. Within the proposed model, this principle is generalized to the case of betavoltaic cells that convert the radioactive beta-decay energy into electricity. The volume-distributed radioisotope source in the form of microparticles is investigated. The efficiency of dissociation and the probability of the recombination of generated charge carriers are calculated. It is shown that the dependence of the device efficiency on the scale parameter of the mixture has a maximum, which determines the optimal structure of the three-dimensional heterojunction.