Photoluminescent and electroluminescent properties of phenol-pyridine beryllium and carbonyl polypyridyl Re(I) complexes codeposited films

The codeposited films of BePP2 (PP=2-(2-hydroxyphenyl)-pyridine) and (Butbpy)Re(CO)3Cl (Butbpy=4,4′-bi(tert-butyl)-2,2′-bipyridine) were prepared by vacuum evaporation deposition. The photoluminescent and electroluminescent properties of the films were investigated. The films with different (Butbpy)Re(CO)3Cl concentration were employed to study the energy transfer properties between BePP2 and (Butbpy)Re(CO)3Cl. Experimental results showed that energy transfer from BePP2 to (Butbpy)Re(CO)3Cl took place in the codeposited films. The films which were excited optically, exhibited complete energy transfer if (Butbpy)Re(CO)3Cl concentrations were equal or higher than 9%. Under electrical excitation, complete energy transfer were observed when (Butbpy)Re(CO)3Cl concentrations were equal or higher than 3%. The devices of (ITO/TPD (500 Å)/BePP2:(Butbpy)Re(CO)3Cl (500 Å)/Al (2000 Å)) which contained the codeposited film with (Butbpy)Re(CO)3Cl concentration of 50%, showed maximum EL efficiency value of 1.6 lm/W and maximum lightness of 6500 cd/m2.