Electric field effect on luminescence, and photoconduction in electron donor-electron acceptor organic solid films

The electric field-induced exciplex photolumniescence quenching (up to 80%) is accompanied by remarkable photocurrents (up to 1 mA/cm(2)) in undoped and a (PtLCl)-Cl-2 (L = organic ligand) complex-doped blends of a starburst amine of m-MTDATA used as an electron donor and bathophenathroline (BPT) used as an electron acceptor. These results are rationalized by efficient dissociation of singlet (1)\m-MTDATA:BPT] and triplet (3)\m-MTDATA:(PtLCl)-Cl-2] exciplexes, and molecular excitons (1)(m-MTDATA) of the donor being exciplex precursors. While the dissociation determines the photoconduction of the blends, the interaction of molecular singlet excitons, (1)(m-MTDATA), with the photogenerated charge is the process that largely controls the quenching effects.