InxGa1−xAs thermophotovoltaic cell performance vs bandgap

Abstract

Measured data is presented on six compositions of indium gallium arsenide (InxGa1−xAs) thermophotovoltaic (TPV) cells with bandgaps of 0.74, 0.68, 0.64, 0.59, 0.55 and 0.5 eV. The cell structures were identical, the only difference being the bandgap of the cell emitter and base layers. The tradeoff in electrical output versus cell bandgap was examined when the cells were illuminated with a 1000 °C blackbody. The 0.64 eV bandgap (In0.62Ga0.38As) cells had the highest power output, representing a compromise between the higher photocurrent (but higher dark current) lattice‐mismatched lower bandgap cells and the higher photovoltage, lower dark current, lattice‐matched In0.53Ga0.47As higher bandgap cells.