The efficiency and time-dependence of luminescence from poly (p-phenylene vinylene) and derivatives

✍ Scribed by I.D.W. Samuel; B. Crystall; G. Rumbles; P.L. Burn; A.B. Holmes; R.H. Friend

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 697 KB
• Volume: 213
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)89144-7

✦ Synopsis

We report measurements of the quantum efficiency and time decay of photoluminescence in the conjugated polymers poly(g phenylenevinylene) (PPV) and poly(Z-methoxy, 5-(2'ethyl-hexyloxy)-p-phenylenevinylene) (MEH-PPV). MEH-PPV is soluble and we measure values for the quantum yield for luminescence of order 35% for dilute solutions in toluene and chloroform. By comparison of luminescence decay rates in solution and in solid films we estimate luminescence efticiencies in solid films, which can be as high as 50% in partially conjugated PPV. Decay time distribution analysis of the luminescence reveals a broad distribution of decay rates, and this is consistent with the distribution of conjugation lengths known to be present in these materials. Exciton migration in better conjugated material results in narrower distributions of emitting chromophores.