All-perylene-derivative for white light emitting diodes.

An organic-based bright white light emitting compound, namelyTb(H3PTC)(3)[H4PTC = perylene-3,4,9,10-tetracarboxylic acid], able to be used as part of a white diode and as a part of a RGB system that can withstand high temperatures (similar to 700 K), is developed using perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) and terbium(iii) nitrate pentahydrate as precursors by hydrothermal synthesis. UsingPTCDAas the red emitter and the new derivative of it,Tb(H3PTC)(3), as the blue-green emitter, along with a common deep blue LED can form a RGB system for display technologies, around room temperature. Temperature-dependent photoluminescence properties of theTb(H3PTC)(3)compound are also investigated for the involved excitonic-emission processes and the respective recombination lifetimes. The terbium(iii) complex was prepared using a procedure that is reproducible, easily modifiable, inexpensive, and environmentally friendly, opening new pathways for its large-scale applications. UnlikePTCDA,Tb(H3PTC)(3)has been shown to be soluble inN-methyl-2-pyrrolidone (NMP) as well as in dilute aqueous solutions of this organic solvent in a straightforward procedure. The light emission properties are intimately correlated with the molecular structure and electronic properties ofTb(H3PTC)(3)elucidated by experimental results of X-ray Absorption Near Edge Spectroscopy (XANES), Extended X-ray Absorption Fine Structure (EXAFS) and Density Functional Theory (DFT) calculations. A bright fluorescence yield is attained with a small amount of material either in solution or in solid form showing its potential to be used in state-of-the-art organic optoelectronic devices.