Contact electrification by collision of homogenous particles

Contact electrification by collisions of homogenous particles is investigated by two-particle collision experiments, which reveals the relation between electrification and the diameter ratio and relative colliding velocity of the two particles. Then, based on researches reported by Grzybowski's research group, a statistical model to compute the net charge of electrified particle after a single collision and multiple collisions are established, respectively. The model shows the net charge carried by the electrified particles depends on the difference between the two surfaces’ areas involved in collision contact and gives results in good agreement with our experiment results.