A novel series of monodisperse bis-dipolar emissive oligoarylfluorenes, OF(2)Ar-NPh, bearing an electron affinitive core, 9,9-dibutylfluorene as conjugated bridges, and diphenylamino as end-caps was successfully synthesized by a convergent approach using palladium catalyzed Suzuki cross-coupling. The results of optical and electrochemical investigations showed that the HOMO, LUMO, and energy gap of these diphenylamino endcapped oligoarylfluorenes can easily be modified or tuned by the use of various electron affinitive central aryl cores that included dibenzothiophene, phenylene, oligothiophenes, 2,1,3-benzothiadiazole, 4,7-dithien-2-yl-2,1,3-benzothiadiazole, thiophene S,S‘-dioxide, and dibenzothiophene S,S‘-dioxide as well as the extent of the π-conjugated core. As a result, their emission bands measured in chloroform can cover the full UV−vis spectrum (from 412 to 656 nm). In contrast to the common dipolar chromophores, most of OF(2)Ar-NPhs can form morphologically stable amorphous thin films (T g = 88−127 °C) with a high decomposition temperature, T dec > 450 °C. Remarkably, undoped OF(2)Ar-NPh-based multilayer OLEDs could exhibit good to excellent device performance with emission colors spanning the full UV−vis spectrum. OF(2)Ar-NPh bearing oligothiophene core based devices exhibit a maximum luminance of 5000−12500 cd m-2 and luminous efficiency up to 3.6−4.0 cd A-1. Our findings provide a practical approach to design and tune the color emission of efficient and potentially useful light emitting materials.

Three new 2,2'-dipyridylamino functionalized pyrene derivatives, 1-pyrenyl-2,2'-dipyridylamine (1), 4-(1pyrenyl)phenyl-2,2'-dipyridylamine (2), and 4-[4'-(1-pyrenyl)biphenyl]-2,2'-dipyridylamine (3) have been synthesized and fully characterized. For comparison of electronic properties, a diphenylamino functionalized molecule 4-[4'-(1-pyrenyl)biphenyl]diphenylamine (4) has also been synthesized. Compounds 1-4 are bright blue emitters in solution and in the solid state with l max at y420-460 nm and a high emission efficiency in solution. All four compounds form amorphous glasses with T g values of 66 uC, 79 uC, 165 uC, and 98 uC, respectively. The electronic properties of the four compounds were examined by spectroscopic methods, cyclic voltammetry and Gaussian 98 molecular orbital calculations. The utilities of this class of molecules in OLEDs have been demonstrated by EL devices of compounds 3 and 4, which showed that 3 can function as a bright blue emitter and an electron transport material in a double-layer device while 4 can function as a bright blue emitter and a hole transport molecule in a triple-layer device. The dipyridylamino functional group in molecules 1-3 are capable of chelating to metal ions such as Zn(II) as demonstrated by the synthesis and structure of the complex [2?(Zn(O 2 CCF 3 ) 2 ] 2 (5). The binding of Zn(II) ions to the dipyridyl group causes a reduction of the emission efficiency of the ligand 2.

A facile approach for synthesis of bipolar oligofluorenes, TAZ-OF(n)-NPh, n = 2 or 3 end-capped with hole-transporting diphenylamino and electron-transporting triazole moieties by Suzuki cross-coupling as the key reaction has been developed. This novel bipolar oligofluorenes exhibited blue-emission, high thermal and morphological stabilities. The single-layer OLED based on TAZ-OF(2)-NPh exhibited superior device performance with a maximum luminance of 1128 cd m(-2) and luminance efficiency of up to 0.83 cd A(-1).

A new broadband UV light‐based processing method for a screen printable silver oxalate molecular ink is developed that enables structural electronics to be produced on complex thermoformed 3D objects. The production of these 3D devices is driven by the light‐induced reduction of silver oxalate to form an interfacial silver nanoparticle layer that allows the ink to transition to a viscous liquid intermediate and elongate up to 50% without cracking during thermoforming. Ultimately, this enables the development of 3D electronics devices with significantly less limitations on geometry, shape, size, and depth in comparison to commercially available inks. UV processing is also effective for 2D traces on low temperature PET substrate, where in situ produced silver nanoparticles can subsequently absorb light and further facilitate the rapid conversion of the silver oxalate to metallic silver through a self‐limiting thermal decomposition. The resulting traces have superior electrical properties and are produced in significantly less time in comparison to thermal sintering. Together, UV processing and the silver oxalate molecular ink serve as a platform for both the rapid production of conductive silver traces on low temperature substrates and the development of novel thermoformed 3D human‐machine interface devices, areas of interest for both academia and industry.

In addition to hole transport, diphenylamino-end-capped oligofluorenylthiophenes can exhibit efficient electron transport, in which the oligothiophene central core acts as an excellent electron-transporting moiety. The highly efficient undoped multilayer OLEDs using OF(2)TTP-NPh and OF(2)QTP-NPh as an electron-transporting emitter exhibited a maximum luminance of 19,800 and 11,800 cd m(-2) with a luminance efficiency up to 5.3 and 1.0 cd A(-1), respectively.