Enhanced low-gap thermophotovoltaic cell efficiency for a wide temperature range based on a selective meta-material emitter

The concept of thermophotovoltaic system, based on a compact selective meta-material film structure acting as a selector thermal blackbody radiation emitter, is presented. The meta-material (MTM) film exhibits broad-band thermal radiation absorption with selective narrow-band thermal infrared emission, and can thus be efficiently coupled to a tandem (InAs/GaInAsSb) thermophotovoltaic (TPV) cell, which has based on the experimentally sub-cells data. The TPV tandem cell combined with the selective emitter achieves highest TPV conversion efficiency of 41% for black body radiation temperature (T-BB) = 1500 degrees C, and lowest TPV conversion efficiency of 11.82% for T-BB = 300 degrees C. The TPV combined system thus operates in wide temperature range of 300 degrees C to 1500 degrees C, and the combined system shows higher performance when the MTM film is included. It also shows much higher performance than literature values reported for GaSb/GaInAsSb tandem thermophotovoltaic cells having no MTM film.