Article

Toward high-energy-density, high-efficiency, and moderate-temperature chip-scale thermophotovoltaics.

Research Laboratory of Electronics, Institute for Soldier Nanotechnologies, Department of Physics, Center for Materials Science and Engineering, and Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 02/2013; DOI: 10.1073/pnas.1301004110
Source: PubMed

ABSTRACT The challenging problem of ultra-high-energy-density, high-efficiency, and small-scale portable power generation is addressed here using a distinctive thermophotovoltaic energy conversion mechanism and chip-based system design, which we name the microthermophotovoltaic (μTPV) generator. The approach is predicted to be capable of up to 32% efficient heat-to-electricity conversion within a millimeter-scale form factor. Although considerable technological barriers need to be overcome to reach full performance, we have performed a robust experimental demonstration that validates the theoretical framework and the key system components. Even with a much-simplified μTPV system design with theoretical efficiency prediction of 2.7%, we experimentally demonstrate 2.5% efficiency. The μTPV experimental system that was built and tested comprises a silicon propane microcombustor, an integrated high-temperature photonic crystal selective thermal emitter, four 0.55-eV GaInAsSb thermophotovoltaic diodes, and an ultra-high-efficiency maximum power-point tracking power electronics converter. The system was demonstrated to operate up to 800 °C (silicon microcombustor temperature) with an input thermal power of 13.7 W, generating 344 mW of electric power over a 1-cm(2) area.

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