Simulation of temperature-dependent material parameters and device performances for GaInAsSb thermophotovoltaic cell

Temperature-dependent material parameters and device performances of GaxIn1−xAs1−ySby TPV cells applied in low temperature (800–1200 °C) radiators are simulated using the PC-1D. As is well known, the optimum bandgap (Eg) decreases towards lower radiator temperatures. So far, the lowest achievable Eg of GaxIn1−xAs1−ySby at 300 K is 0.5 eV. We mainly considering the Ga0.8In0.2As0.18Sb0.82 (Eg = 0.5 eV) TPV cell. The effects of doping concentration and recombination mechanisms of the emitter layer on photovoltaic conversion efficiencies (ηcel) are analyzed in detail, and ηcel can be improved by optimizing doping concentration and suppressing carrier recombination. The effects of GaSb window layer on ηcel are also presented. It shows the type-II energy-band alignment GaSb(window)/GaInAsSb(emitter) heterostructure affect ηcel mainly through Voc. For the first time, the effects of operating temperatures on device performances are analyzed based on temperature-dependent material parameters, and the temperature coefficients of the device performances are presented.