Charges are transferred by electrons which we all know. But why can't it be transferred by protons? Well, I searched on Google where I found similar questions already being asked on many sites. However, I didn't find any answers. They were saying that electrons are mobile and similarly protons are busy being nucleons. Also, someone was saying, "By the simple mechanism of separating two things, electrons are pulled out of their Fermi energy levels and into a conduction band to effect charge transference and the creation of a static charge" which I didn't understand at all.
[Physics] Why is the charge transferred by electrons and not by protons
chargeconductorselectricity
Best Answer
You can totally transfer charge using protons. Or using Na+ or any kind of charged particle. It happens all the time - if you look at how a wet cell battery works, you'll find that while charge across the wire is carried by electrons, current flows along the salt bridge via charged ions (theoretically protons could be among these). I bet if you could somehow make a superfluid out of He+ or something you could use that to carry charge like a superconducting wire.
I think our intuition that electrons are always the charge carriers comes from the fact that:
1.) electrons are very light compared to protons, so if you imagine putting a proton in an electric field and an electron in the same electric field, the electron will be accelerated 1000x more (same charge, 1/1000th the mass). This means that when there is a charge imbalance and either proton or electron flow could alleviate it, the electrons will flow way before the protons are impelled to move.
2.) electrons are the mobile charged particles in a solid - all the protons are bound in nuclei. Since almost all of our intuition about current flow comes from wires or other solid conductors, we're almost exclusively worrying about electron flow.