Organic Photoconductors. I. The Kinetics of Photoconductivity in Rhodamine B

Abstract

The behavior of rhodamine B undergoes a change at about 60°C below which temperature it is complicated by memory effects. Above 60°C the decay process is strictly bimolecular. Three activation energies were measured: for conduction, for decay, and for rise of conductivity, and each was approximately 0.55 ev. The observed second‐order character and the absolute rate of the decay process can be accounted for by a model having a large density of monoenergetic traps lying 0.55 ev below the conduction band. There is evidence that the slowness of reaching a steady state in light is to be associated with a redistribution of charge carriers from the random sites in which they are formed into preferred sites or configurations.