Titanium Tritide Films as Betavoltaic Power Sources

Tritium betavoltaics are one of the family of nuclear batteries which convert natural radioactive decay from a radioisotope into electricity that can provide continuous power without the requirement for replacement or recharging. Tritium is ideally suited to this application due to its high specific activity, low shielding requirements and relatively high availability. Owing to safety and environmental concerns over tritium leakage, metal tritides films are preferred as tritium betavoltaic sources. Titanium hydride and deuteride films were studied as analogues to titanium tritide films. The quality of the films depended on the temperature of hydrogen loading as films loaded at elevated temperatures (>100 °C) were brittle and delaminated from the semiconductor substrate while those exposed to hydrogen at room temperature continued to adhere to the substrate. For the latter films, evidence of hydrogen isotope loss was observed when left under ambient conditions over the course of a few weeks.