Blue-green LEDs from poly(phenylenevinylene) grafted with poly(ethylene imine): improved stability and coordination of transition metals

Abstract

Light emitting diode devices prepared from poly(phenylenevinylene) grafted with poly(ethylene imine) show blue shifted spectra (λ_max≈475-490 nm) proportional to the ratio of the grafted to ungrafted segmers and significantly (up to sevenfold) improved lifetimes; further coordination of transition metals led to increased electroluminescence intensity.

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