High-efficient betavoltaic batteries using graphene coated TiO2 nanotube arrays

Betavoltaic batteries are promising sustainable energy sources for the application of autonomous wireless sensor microsystems. The bottleneck is their relatively low energy efficiency and sustainability. In this work, we report a novel betavoltaic device with significant conversion efficiency using electrochemically reduced graphene oxide (ERGO) on TiO
₂
nanotube arrays (TNTAs) for capturing beta-energy as well as energy conversion. A 10 mCi of
⁶³
Ni source with area of 10 × 20 mm
²
was assembled to graphene on TNTAs (G-TNTAs) to form the sandwich type betavoltaic devices. By I-V measurements, the optimum betavoltaic device exhibits a significant effective energy conversion efficiency of 26.55% with open-circuit voltage of 2.38 V and short-circuits current of 27.18 nA. The experimental results indicate that G-TNTAs are high-potential nanocomposite for developing betavoltaic batteries.