If I had a strong source of radio-frequency photons, can these be converted to electricity like a solar panel does for light?
If I had a strong source of radio-frequency photons, can these be converted to electricity like a solar panel does for light?
Yes, these devices exist. But, IR is significantly, even several orders of magnitude, less powerful from the sun than visible and UV light. The only applications derive from receiving power from human sources that are bright enough, some examples are here in the other comments.
Even then, I have doubts that human IR emitters produce enough power for anything but the most highly efficiently engineered device, outside of a microwave.