In my 8th grade physics class long ago the instructor told us if we were to take a small toy motor and spin its shaft by some mechanism it will produce small electric current, which obviously is the other way around usually.
I asked him if i could take one motor and power it with a battery then couple that motor with another motor will that provide enough current after some time to then power the first motor without battery? He said try it in your next lab.
I sure did, and the results? As soon as I disconnected the battery the first motor always went off even though in my (erroneous ) theory the other motor which was spinning at the same speed should have been sending some current to keep the system working.
So no, if you cant really power such a tiny milliamps motor like that forget about a motor which will power a big propeller for sustained flight.
My R/C aircrafts drain amperes like anything and the quicker you want to recharge them the more power your charger requires and that certainly can not come from those motors themselves.
Yes you can design your aircraft to be able to self charge to increase its flight duration up-to a certain extent and a number of electric aircrafts do this already but that can be a little extension and not self sustained for any considerable duration. KERS does that, Ram Air turbines do that. Even gliders have dynamo to that effect but they don't provide as much power as would be required by your proposed idea