BLUE ELECTROLUMINESCENT DEVICES BASED ON SOLUBLE POLY(P-PYRIDINE)

We have fabricated unilayer electroluminescent devices from soluble po ly(p-pyridine) (PPy). The solubility of PPy in weak acids allows direc t spin casting of the polymer films, The electroluminescence spectrum peaks at 2.5 eV (497 nm) corresponding to white light weighted towards the blue end of the spectrum. The photoluminescence spectrum peaks at 2.35 eV (530 nm). The operating voltages of the devices ranged from 4 to 12 V with current densities of 6 to 8 mA/mm(2). We compare our dev ices with similar blue emitting devices based on poly(p-phenylene). (C ) 1995 American Institute of Physics.