Scintillator based nuclear photovoltaic batteries for power generation at microwatts level

A nuclear photovoltaic battery uses scintillator to convert radiation into visible light, which is then collected by a photovoltaic (PV) cell to generate electricity. If the radiation is gamma-rays emitted from external sources, the battery may also be referred as gammavoltaic battery. In this study, a polycrystalline CdTe solar cell was optically coupled with a 2.0 cm × 2.0 cm × 1.0 cm Gadolinium Aluminum Gallium Garnet (GAGG) scintillator, and the resulting device was tested using intense gamma radiation fields from a Cs-137 (1.5 kRad/h) and a Co-60 (10 kRad/h) irradiator. Measurements with Cs-137 provided a maximum power output (P max ) of ∼288 nW, with a short-circuit current density (J sc ) of ∼1.22 μA/cm 2 and an open-circuit voltage (V oc ) of ∼0.34 V. In contrast, Co-60 irradiator gave a P max of 1.5 μW, with a J sc of ∼4.73 μA/cm 2 and a V oc of ∼0.38 V. The CdTe was also paired with a Lutetium-Yttrium Oxyorthosilicate (LYSO) crystal and tested with the Cs-137 source. The experiment presents a scalable option to reach to higher power outputs by harvesting gamma radiation fields in many cases where high radiation field demands heavy shielding and is often regarded as unwanted waste. • Demonstrated nuclear photovoltaic battery that converts gamma rays into electricity. • Fabricated and tested a prototype of GAGG scintillator coupled with a CdTe PV cell. • The highest power output is 1.5 μW power under 10 kRad/h.