Naive question, wouldn't this (converting Brownian motion into electricity) violate the 2nd law of thermodynamics?
(edit, this is explicitly addressed further in the article: That's an important distinction, said Thibado, because a temperature difference between the graphene and circuit, in a circuit producing power, would contradict the second law of thermodynamics. "This means that the second law of thermodynamics is not violated, nor is there any need to argue that 'Maxwell's Demon' is separating hot and cold electrons," Thibado said.)
This sounds like a mangled explanation. It seems to me, somewhat naively, that the resonator must be held at a higher temperature than the rest of the circuit to produce work on the load.
I think some minuscule amount of energy is taken from the thermal bath (the environment is considered a thermal bath - you can take heat from it and it's so big its temperature won't budge), converted into electricity and then back to heat in the load resistor. They all remain in the same temperature if I'm not gravely mistaken.
(edit, this is explicitly addressed further in the article: That's an important distinction, said Thibado, because a temperature difference between the graphene and circuit, in a circuit producing power, would contradict the second law of thermodynamics. "This means that the second law of thermodynamics is not violated, nor is there any need to argue that 'Maxwell's Demon' is separating hot and cold electrons," Thibado said.)