| Up to date, Flat Panel Displays (FPDs) are playing important roles for mankind to get information and their effects are significant. Organic light-emitting devices (OLEDs) are important members of FPDs and attract world wide attention in the fields of science and industry due to their many merits of light weight, low cost, broad visual angle, high response speed, spontaneous light-emitting, high brightness and efficiency, etc. Since C. W. Tang, et al. reported the high brightness OLEDs at low operating voltage for the first time in 1987, many progress have been made recently. By the use of novel materials, suitable structures and the efforts of world-known companies, OELDs are being moved out of the laboratory and made into commodities. Although the performances of some OLEDs are high, further improving the performances of OLEDs are still the research focus in the world.The excellent properties of OLEDs can't exist if there are nocorresponding materials, and it is clear that the development of small molecular materials have been made great progress in recent years. For full-color applications, the development of red-, green-, and blue-emissive materials with sufficiently high luminous efficiency and proper chromaticity is required. While green-, and blue-emissive materials with good material strength have been achieved, red-emissive materials largely remain crystalline and require cumbersome doping methods in OLED fabrications. Low efficiency and short lifetime, these lead to the red emissive materials can't be used widely. In order to overcome these drawbacks, we set out to explore a series of new red-emissive materials, and there are many other scientific research institutions including domestic and foreign institutions are developing their own representative emitting materials.In this paper, we illustrate the porphyrin derivatives at three aspects: 1) The phosphorescent porphyrin materials, 2) The fluorescent porphyrin materials, 3) the energy-transfer porphyrin luminescent materials. We have conducted our research based on partial porphyrin molecules, and that result in high-efficiency electrophorescence in organic light-emitting devices (OLEDs). The content are showed as follows:About the new system of the phosphorescent porphyrin materials, Forrest et al. reported three porphyrin molecules (PtTNP, RuTPPCO, PtTFjoPP) in1998, these compounds were synthesized under anhydrous and non-oxygen condition. Ultraviolet absorption spectrometry, element analysis and nuclear magnetism spectrogram were used in the token of these porphyrin molecules. Heavy-metal complexes, such as the transition metal2004platinum and ruthenium, can strengthen spin-orbit coupling and shorten the radiative lifetime, it can results in high-efficiency electrophosphorescence in OLEDs. In addition, the high triplet energy of the ligands causes backward energy transfer to the host molecules, this leads to their maximum external quantum efficiencies. Concentration quenching, as a result of interaction among molecules at high concentration, is a common and serious problem for molecular-based emissive materials in organic light-emitting diodes. Red-emissive molecular materials are usually polar, such as electron donor-substituted pyran-containing compounds, or extensively -conjugated compounds, such as porphyrins. These red emitters have an inherent tendency to crystallize and become either weakly emissive or not emissive at all in the solid state, so the bulky naphthyl substitution on the PtTNP molecule can reduce the concentration in solid state, this can lead to the high quantum efficiency. We envisage that fluorinated porphyrins will exhibit improved stability with regard to oxidative deterioration, so we synthesize the high phosphorescent platinum (PtF20TPP) EL devices at different doping concentrations of the PtF20TPP emitter have been fabricated .In these devices, BePP2 and AIq3 act as the host materials, hence the following EL device structure is prepared: ITO / CuPc / NPB / PtTNP: BePP2 / LiF / Al. When 8 % of...
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