Selective Emitter, Thermophotovoltaics, Indium Tin Oxide, Micro-Combustor
Summary / Abstract:
The ideal spectral shape of a TPV emitter requires a high emission with a moderate bandwidth at an energy that is slightly above the semiconductor diode bandgap. Long wavelength suppression is also essential to prevent the energy losses due to the transparency of the diode for photons with energy smaller than the semiconductor bandgap. The properly tailored spectral emission enhances the overall efficiency of a typical TPV system. While in recent years there have been many remarkable efforts in far-field TPV using various photonic nanostructures, here we used a simple planar emitter structure using indium tin oxide (ITO) on sapphire, which can achieve the desired emission characteristic as an ideal TPV emitter. In addition, we demonstrate a stainless-steal/quartz micro-combustor that can be used in conjunction with ITO/Sapphire selective emitter. The mixture of 1:1 CH4/H2 fuel in the micro-combustor leads to stable combustion. Additionally, when the exit temperature is larger than 1000 K and the bright incandescent feature appears in the channel surface, we can infer the coexistence of heterogeneous and homogeneous reaction in the reactor. It is noted that catalytically induced flame can be anchored inside the micro channel, and flame luminosities in the micro reactor are apparently bright in equivalence ratio of 1.0 and 0.8.