
Rice University carbon nanotube device channels heat into light - goodmachine
https://news.rice.edu/2019/07/12/rice-device-channels-heat-into-light/
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olliej
What frequencies are they able to redirect to? My understanding that
photovoltaics have specific frequency ranges that are more efficient, but the
paywalls mean I can’t tell what frequencies they’re currently able to target
not how tunable this might be. I can’t imagine it’s visible light because that
would seem like press-release gold

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mechagodzilla
Solar cells have a band gap energy which corresponds to a specific frequency
of light. Photons below that frequency don’t knock any electrons loose (they
just make heat) and photons above that frequency still only knock one electron
loose (and the rest of the energy goes to heat). So a single band gap cell is
limited to 20-something % max efficiency as a theoretical limit. The ability
to re-emit heat at a specific frequency (that could be fed into a cell tuned
for that frequency) would be really neat.

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olliej
I recall an article last week (I think?) about a team managing to get multiple
electrons (?) from a single photon, so it seems like would could put
everything together and get a decent (overall %) efficiency increase - though
I’m sure none of these are particularly close to mass production/deployment

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stubish
Would this be useful as a cooling device?

