A method for improving the betavoltaic cell’s conversion efficiency: Using the alloy as Schottky metal

Under the irradiation of a 63Ni source, the Al/diamond Schottky barrier diode and 2198 Al–Li alloy/diamond Schottky barrier diode can convert decay energy into electrical energy. Through the Monte Carlo method, the energy depositions of the 63Ni source in the energy converters are simulated separately. And then the electrical output properties of two betavoltaic batteries are calculated and compared. The short-circuit current density, open-circuit voltage, fill factor and maximum output power density of the Al/diamond and 2198 Al–Li alloy/diamond Schottky barrier batteries are 0.086 μA/cm2, 2.14 V, 0.93, 0.17 μW/cm2 and 0.089 μA/cm2, 2.66 V, 0.95, 0.22 μW/cm2, respectively. The maximum output power increased by about 29%, which indicates that using alloy as Schottky metal can significantly improve the output performance of a betavoltaic battery.