film. In addition, the composite film highly enhances the EL intensities. The PDOF/nanoporous silica nanocomposite film exhibits narrow emission spectra, along with PL spectra that are more thermally stable, compared to the spectra of a neat PDOF film. This pure emission is attributed to the reduced number of keto-type defects in the polymer chains. In short, three-dimensional nanocomposite material is potentially one of most effective candidates for devices that emit blue light; it has good environmental stability, high efficiency and good colour purity.

Acknowledgments

The authors wish to thank Professor Ryong Ryoo and the Department of Chemistry, Korea Advanced Institute of Science and Technology, Korea. The authors are also grateful to the Center for Advanced Functional Polymers.

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