We develop high efficiency solution-processed pure green organic light-emitting devices using a starburst molecule 7,7′,7″-(5,5,10,10,15,15-hexahexyl-10,15-dihydro-5H-diindeno[1,2-a:1′,2′-c]fluorene-2,7,12-triyl)tris(4-(4-(9H-carbazol-9-yl)phenyl)benzo[c][1,2,5]thiadiazole)(TRcz)doped 2-methyl-9,10-di(2-naphthyl)anthracene(MADN)as the emitting layers.The electroluminescence properties of the devices with different doping concentrations are investigated.With the increasing doping concentration from 0.5wt%to 5wt%,the maximum efficiency changes from 4.8cd/A to 8.4cd/A.Under the optimal concentration of 4wt%,the device shows pure green emission at 516nm with a chromaticity coordinate of(0.30,0.59)as well as a high brightness of 19900cd/m^(2)and a high efficiency of 10.1cd/A,which are better than 11490cd/m^(2)and 4.2cd/A obtained in the undoped device.
A new star-shaped oligoelectrolyte (TEFCOONa) with triphenylamine as the core, acetylene as linkage and anionic fluorenes as arms was obtained and used for direct imaging in living PANC-1 cells. Because of the hydrophobic conjugated groups of the oli-goelectrolyte, TEFCOONa can form nanospheres with an average diameter of^75 nm in 10 mmol/L PBS. These nanospheres possess a relatively high absolute quantum yield (16.5% in PBS), low cytotoxicity and can penetrate into the nucleus through the cytoplasm, which is essential for living cellular imaging. Collectively, these results validate our rational design of conjugated oligoelectrolyte and even hyper branched polymers-copolyelectrolyte as effective nanovectors for bioimaging and other clinical applications.
SONG WenLiJIANG RongCuiYUAN YanLU XiaoMeiHU WenBoFAN QuLiHUANG Wei
