Blue emission from polymer nanocomposites: preparation and application of multicolored luminescent materials

Blue-emitting luminescent polymer nanocomposites were prepared from 1,3-diketone functionalized poly(methyl methacrylate) (PMMA) and zirconium oxide nanocrystals (ZrO2-NCs). Fourier transform infrared spectra suggested chemisorption of the 1,3-diketone by bidentate chelation of the diketonate anion to the ZrO2-NC surface. The ZrO2-NCs were well dispersed in the polymer matrix and crosslinked on the NC surfaces. The chemically crosslinked polymer nanocomposites had high photostability compared with the PMMA/ZrO2-NC composites with 1,3-bis(4-methoxyphenyl)-1,3-propanedione. The stability of the luminescence from the polymer nanocomposites was enhanced because the 1,3-diketonate binding sites were fixed between inorganic NCs and polymer chains. The blue emission peaking at 448nm can be tuned by the addition of 8-hydroxyquinoline-containing copolymer/ZrO2-NC composite, which red-shifted the emission from blue to yellow and green as a function of the blend composition. This strategy, in which the ligand would be immobilized by an organic/inorganic sandwich structure, is suitable for obtaining not only well-stabilized luminescent nanocomposites but also nano-optoelectronics with controlled emission colors. Polymer Journal (2011) 43, 352-357; doi:10.1038/pj.2010.144; published online 9 February 2011