Comparison and study of the preparation methods for phosphor layer in nuclear battery

Abstract

This work investigated the preparation and optimization of phosphor layer for radioluminescent nuclear battery, and analyzed the property change of the phosphor after irradiation. ZnS:(Cu, Al) with grain size of 5 μm was selected as the phosphor material, and AlGaInP semiconductor was used as the photovoltaic unit. Monte Carlo modeling was used to simulate energy deposition, absorbed dose, penetration of β particles in the phosphor. The optimized coupling scheme of radioisotope sources and phosphor layer was obtained based on comparison particle penetration depth and the output power of radioluminescent nuclear battery. The phosphor layer with 60Co γ-radiation enhanced the luminescence property up to 50% at the radiation dose of 871 kGy, which is considered as an optimized method of phosphor layer preparation. The radiation of 10 MeV electron was conducted to study the degradation based on the microscopic lattice characteristics, morphological changes, optical and electrical properties. Phosphors have excellent radiation resistance. The output power of nuclear batteries has only declined by 43% even when electron radiation dose reaches 8.56 MGy. The prospect for utilizing ZnS:(Cu, Al) phosphor as radiant energy conversion materials in nuclear battery was also discussed. Results provided an effective guideline for predict the service conditions of radioluminescent nuclear battery.