I'm currently working on a humidity sensor based on nanocrystalline graphite material, and we suspect that the sensing mechanism is due to protonic conduction of surface adsorbed water molecules, causing shunt between graphene crystals on the film surface. In literature, I notice most researchers used DC resistance measurements, and this is what I've done.

However, in most electro-chemical sensors (liquid based ones) where ionic conduction happens, impedance measurements (AC ) was used instead. This is done to prevent charge accumulation. So my question is, in a relative humidity sensor, will charge accumulation be of any concern?