Mn2+ Induced Significant Improvement and Robust Stability of Radioluminescence in Cs3Cu2I5 for High Performance Nuclear Battery

Abstract

Fluorescent type nuclear battery (NB) consisting of scintillator and photovoltaic device (PVD) enables semipermanent power source for both small and large devices working under harsh circumstances without instant energy supply. In spite of the progress of device structure design, the development of scintillators with high light yield (LY) and longer emission wavelength catering to PVDs is far behind. Here, a novel Cs3Cu2I5: Mn scintillator, which exhibits an ultrahigh LY of ~ 67000 ph/MeV at an emission wavelength of 564 nm is presented, and this is the highest value at such a long wavelength based on low cost precursors. Besides, doping and intrinsic features endow Cs3Cu2I5: Mn with robust thermal stability and irradiation hardness that 71% or > 90% of the initial radioluminescence (RL) intensity can be maintained in an ultra-broad temperature range of 77 K-433 K or after a total irradiation dose of 38.7 Gy at 333 K, respectively. These superiorities allow the fabrication of an efficient and stable NB, which showed an output improvement of 337% respect to that without scintillator. Luminescence mechanisms including self-trapped exciton, energy transfer, and impact excitation are proposed for the dramatic RL improvement. It is expected that such a new and robust scintillator will open a window for the fields of NBs and radiography.