Studies on synthesis and EL properties of several novel squaraines

Several novel squaraines were synthesized and their structures were elucidated by IR, HNMR, MS and elementary analysis. Their photoluminescent (PL) and electroluminescent (EL) properties have been studied, which indicated that all of them had electrontransporting properties, and some had both electron, and hole-transporting properties. One of the squaraines was inserted between a cathode and an anode, and the single-layer-sandwiched device processed a redlightemitting ability under both low negative and low positive driven bias. It was regarded as one kind of promising material.