The devices of polymer mixed with phosphorescence dye have the virtue

of high efficient

easy to fabricate.But our attention should be given to the congregation and phase separation of the small molecule

especially at high concentration.By using a matrix polymer PC (poly[2

7-(9

9-dihexylfluorene)-co-alt-2

10-(cyclohexane-l-spiro-6/-dibenzo [d

f][1

3]

dioxepin)])

a kind of PF (polyflorene) polymers which have twist structure and have broad band gap causing the emission have a blue shift about 20nm than PF

more close to the absorption of Ir(ppy)

3

(iridium(Ⅲ) tri(2-phenylpyridinato-N

C

2

))

that means it can get a better matching between the emission of polymer and the absorption of phosphorescence dye

and achieve higher efficient energy transfer.At low concentration (about 0.5%)

the matrix polymer PC can transfer its total energy to Ir(ppy)

3

.At such low concentration

congregation or phase separation can result less problem.The device structure is ITO/PEDOT:PSS/polymer:Ir(ppy)

3

/Ba/Al.