Electric double layer dynamics by high-field electroluminescence in aqueous solution (Destriau effect)

Abstract

Transient luminescence induced by high electric fields (>2.5 x 10(4) V/cm) was observed in aqueous solutions of 6,8-dihydroxypyrene-1,3-disulfonic acid. The light emission takes place both at the leading and the trailing edges of the perturbing electric square pulse. It occurs only during the variation of the applied field and disappears with a time constant of 0.5 musec at constant field. In solid state phosphors, where this phenomenon has been reported previously, it is known as the Destriau effect. The mechanisms of excitation and emission can be explained by the electron injection model, in which the time constant of the luminescence decay is associated with the rate of formation of the space charge. This space charge appears as a separation of positive and negative charges into a double layer stabilized by the applied potential.