Novel Use of Semiconductive Conjugated Polymer With Optimized Scintillator for Betavoltaic Applications

The ongoing advanced space exploration requires the novel energy sources that can generate power for extreme duration without need of refill. The long duration betavoltaic devices are presented using conjugated polymer with scintillators. The Monte Carlo simulations are used to study the interaction of electron beam with two different scintillators, Cerium doped Yttrium Aluminum Garnet (Ce:YAG) and Thallium doped Cesium Iodide (CsI:Tl). The catholuminescence profiles from simulation showed that CsI:Tl is more-efficient to generate photons when hit by electron beam compared to Ce:YAG. The semiconductive conjugated polymer device stack of ITO/PEDOT:PSS/P3HT:ICBA/Al are then fabricated and tested with Ce:YAG and CsI:Tl scintillators under different electron beam energies. The electrical current is successfully extracted from these betavoltaic devices when illuminated with electron beams. As expected, the betavoltaic devices with CsI:Tl scintillator performed better compared with Ce:YAG. The maximum power conversion efficiency (PCE) of 0.24% is obtained at 10 kV electron beam with CsI:Tl, while PCE in device with Ce:YAG is 0.16%. The short circuit current in devices with CsI:Tl is about 57%, greater than in devices with Ce:YAG. The experimental result showed that output electrical power increased with increase in incident electron beam energy.