Surface conductivity in liquid-solid interface due to image force

The image force is considered to be one of the nonspecific sources of surface conductivity origin in the interface between a non-polar liquid dielectric and a polar solid one. Two possible physical mechanisms have been investigated. The first one takes into account the existence of a potential barrier to the charge movement as it leaves the surface. Therefore the charges that are in liquid are attracted to the surface. The second one is the reduction of dissociation energy of ion pairs close to the interface in comparison with bulk dissociation. Both mechanisms result in a decrease of recombination rate and in a sharp increase of dissociation rate. It has been shown that both these mechanisms could lead to creation and accumulation of an abnormal nonspecific surface charge carrier. Preliminary experimental results don´t contradict theory. Surface conductivity of ceramics with ε=80 in contact with transformer oil (ε=2.3) is sharply increased in case of slight dissociating organic doping.