Betavoltaic battery based on reduced-Graphene-Oxide/Si heterojunction.

This paper presents a new beta converter cell based on reduced graphene oxide (rGO)/Si heterojunction suitable for betavoltaic batteries. The potential barrier created in the rGO/Si interface induces an internal electric field in the Si substrate. This internal electric field can be used for separating the beta-generated electron-hole pairs in Si. Ni63, with the activity of 5mci is used as the beta radioisotope source. The current-voltage characteristic of the cell is measured with and without radioisotope radiations. The circuit model of the junction is also presented. The cell shows an open circuit voltage of 34 mV, a short circuit current of 0.41 μA/cm2, and high conversion efficiency of 3.9% under exposure of beta radioisotope Ni63. The presented structure, additionally, benefits from the capability of graphene in the absorption of beta particles and carrier separation via ununiformed finger shape of front electrodes. • We present a new beta voltaic cell based on reduced Graphene Oxide (rGO)/Si heterojunction. • The cell shows a high conversion efficiency of 3.9% under exposure of beta radioisotope Ni63. • The open circuit voltage and short circuit current of the cell are 34 mV 0.41 uA/cm2 respectively. • In our beta cell, the generated carriers can be collected in Graphene in addition to Si via ununiformed finger electrodes. [ABSTRACT FROM AUTHOR]