Spectral tuning of conjugated polymer colloid light-emitting diodes

Langmuir. 2010 Feb 16;26(4):2945-50. doi: 10.1021/la9027749.

Abstract

In recent years, the importance of the polymer light-emitting diode (PLED) has grown immensely, proving very desirable in numerous applications because of very high efficiencies, low power consumption, and ease of fabrication. Typically, these devices have been constructed in a layered, thin-film fashion consisting of either electron- and hole-transport materials doped with a luminescent dye (Hebner, T. R.; Sturm, J. C. Appl. Phys. Lett. 1998, 73, 1775. Jiang, X.; Register, R. A.; Killeen, K. A.; Thompson, M. E.; Pschenitzka, F.; Hebner, T. R.; Sturm, J. C. J. Appl. Phys. 2002, 91, 6717. Yeh, K. M.; Chen, Y. Org. Electron. 2008, 9, 45-50. Oh, G. C.; Yun, J. J.; Park, S. M.; Son, S. H.; Han, E. M.; Gu, H. B.; Jin, S. H.; Yoon, Y. S. Mol. Cryst. Liq. Cryst. 2003, 405, 43-51. Lee, J. I.; Chu, H. Y.; Kim, S. H.; Do, L. M.; Zyung, T.; Hwang, D. H. Opt. Mater. 2003, 21, 205-210. Hwang, D.-H.; Park, M.-J.; Lee, C. Synth. Met. 2005, 152, 205-208) or a conjugated polymer that can be engineered to tune the emission of the PLED to particular wavelengths. Stable PLED aqueous colloidal dispersions were prepared containing poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene], (MEH-PPV), poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO), and a binary poly(9,9-di-n-octylfluorenyl-2,7-diyl)/poly(2,5-dioctyl-1,4-phenylenevinylene) (PFO/POPPV) particle dispersion. Red-, green-, and blue-light-emitting colloidal dispersions could then be combined to achieve color-tailored emissions spanning the visible spectrum.