Poling Field Strength Dependent Photoluminescence of Disperse Red-19

Photoluminescence of disperse red-19 (DR-19) have been investigated with various poling field strengths. Two step synthetic processes were employed to employ the DR-19 to the TiO
₂
sol-gel including a urethane bond formation between a DR-19 (-OH) and a 3-isocyanatopropyl triethoxysilane (ICPTES, -N=C=O) and the hydrolysis of the ethoxy group from the ICPTES and condensation reaction between silanol groups from ICPTES and TiO
₂
. The composite was coated to the ITO coated glass substrate. Corona poling were performed before drying the composite with various electric field strengths. The photoluminescence also decreased as the poling field increased. There is long luminescence tail for the poled TiO
₂
DR19 film compared with unpoled TiO
₂
DR19 film. The luminescence long tail indicates that the self-trapped excitons and small polarons were generated when the film poled relatively low electric field.