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Near-field radiative thermoelectric energy converters: a review

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Abstract

Radiative thermoelectric energy converters, which include thermophotovoltaic cells, thermoradiative cells, electroluminescent refrigerators, and negative electroluminescent refrigerators, are semiconductor p-n devices that either generate electricity or extract heat from a cold body while exchanging thermal radiation with their surroundings. If this exchange occurs at micro or nanoscale distances, power densities can be greatly enhanced and near-field radiation effects may improve performance. This review covers the fundamentals of near-field thermal radiation, photon entropy, and nonequilibrium effects in semiconductor diodes that underpin device operation. The development and state of the art of these near-field converters are discussed in detail, and remaining challenges and opportunities for progress are identified.

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Acknowledgements

This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences (Grant No. DESC0018369). This material is also based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. (DGE-1650044). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the funding agencies.

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Tervo, E., Bagherisereshki, E. & Zhang, Z. Near-field radiative thermoelectric energy converters: a review. Front. Energy 12, 5–21 (2018). https://doi.org/10.1007/s11708-017-0517-z

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