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Acquiring desirable device performance with deep-blue color purity that fulfills practical application requirements is still a challenge. Bipolar fluorescent emitters with hybrid local and charge transfer (HLCT) state may serve to address this issue. Herein, by inserting anthracene core in the deep-blue building blocks, the authors successfully developed two highly twisted D-π-A fluorescent emitters, ICz-An-PPI and IP-An-PPI, featuring different acceptor groups. Both exhibited superb thermal stabilities, high photo luminescent quantum yields and excellent bipolar transport capabilities. The non-doped OLEDs using ICz-An-PPI and IP-An-PPI as the emitting layers showed efficient blue emission with an external quantum efficiency (EQEmax ) of 4.32 % and 5.41 %, and the CIE coordinates of (0.147, 0.180) and (0.149, 0.150), respectively. In addition, the deep blue doped device based on ICz-An-PPI was achieved with an excellent CEmax of 5.83 cd A-1 , EQEmax of 4.6 % and the CIE coordinate of (0.148, 0.078), which is extremely close to the National Television Standards Committee (NTSC) standard. Particularly, IP-An-PPI-based doped device had better performance, with an EQEmax of 7.51 % and the CIE coordinate of (0.150, 0.118), which was very impressive among the recently reported deep-blue OLEDs with the CIEy

Remote sensing of solar-induced fluorescence (SIF) opens a new window for quantifying a key ecological variable, the terrestrial ecosystem gross primary production (GPP), because of the revealed strong SIF-GPP correlation. However, similar to many other remotely sensed metrics, SIF observations suffer from the sun-sensor geometry effects, which may have important impacts on the SIF-GPP relationship but remain poorly understood. Here we used remotely sensed SIF, globally distributed tower GPP data, and a mechanistic model to provide a systematic analysis. Our results reveal that leaf physiology, canopy structure, and sun-sensor geometries all affect the SIF-GPP relationship. In particular, we found that SIF observations in the sun-tracking hotspot direction can be a better proxy of GPP due to the similar responses of light use efficiency and SIF escaping probability in the hotspot direction to the increasing incoming solar radiation. Such conclusions are supported by a variety of modeling simulations and satellite observations over various plant function types, at different time scales and with satellite observational modes. This study demonstrates the potential and advantage of normalizing SIF observations to the hotspot direction for better global GPP estimations. This study also demonstrates the great potentials of current and future spaceborne sun-tracking satellite missions for a significant improvement in measuring and monitoring, at a wide range of spatial and temporal scales, the changes in terrestrial ecosystem GPP in response to anticipated changes in the Earth's environmental conditions.

Carbon nanodots (CDs) are fluorescent nanomaterials that have attracted widespread attention for biomedical applications. Since different cells possess different membrane potentials, the influence of the trans-membrane potential on the adsorption behaviour needs to be explored extensively. It was found that fewer CDs can be adsorbed by depolarized cells with decreased membrane potential, as compared to hyperpolarized cells with enhanced membrane potential that promotes the adsorption of CDs. A similar adsorption trend was observed for two cell lines, namely NIH3T3 and MCF-7. Since phosphocholine is the primary component of the cellular membrane, the adsorption behaviour of CDs is further complemented by the interactions between CDs and three kinds of liposomes with different surface charges via the thermodynamic and kinetic perspectives. The adsorption constants between negatively charged CDs and liposomes are positively related to their membrane potential, which is similar to the adsorption rate constants. It was further found that the adsorption of CDs onto liposomes was initiated by electrostatic attraction forces. The membrane integrity and fluidity of liposomes exposed to CDs have also been characterized. The membrane potential of cells is, therefore, particularly important when predicting the relative cytotoxicity of CDs and developing CDs-based nanomaterials for biomedical applications.

A cobalt(II) coordination polymer with an unusual 4,4,4-connected network was hydrothermally synthesized and observed with high thermal, solvent, and pH stabilities. This polymer can serve as the first dual-responsive fluorescent chemosensor for the selective detection of acetylacetone and Cr2O72- ion (pH 3.0) in aqueous systems.

A new type of conjugated polybenzimidazole (CPBI) was synthesized through a simple polycondensation reaction without metal catalysis, and N-alkylation modification was carried out to solve the problems of solubility and fluorescence properties. A series of nano-microsphere polymers CPBIn with large conjugation, good solubility, and strong fluorescence has been successfully used as “turn-off” fluorescent probes for the first time. The results show that, under suitable N-alkylation conditions, the obtained CPBIn can be used as a highly sensitive and selective fluorescent probe for the detection of Cu2+ and Zn2+ at the same time, and their detection limits are both nM levels. In addition, CPBI2 can be designed as an ultra-sensitive IMPLICATION logic gate at the molecular level, cyclically detecting Cu2+. With the test paper containing CPBI2, easy and quick on-site detection can be achieved. This research provides a new idea for the brief synthesis of multifunctional materials.

A new fluorescent probe T2 for Zn2+, by employing coumarin and quinoline as the detection platform, was rationally designed and synthesized. Of particular significance was that T2 showed a specific colorimetric and ratiometric response towards Zn2+ without interference from other biologically important cations. T2 also displayed high affinity towards Zn2+ ions with a Kd of 0.98 μM with a visually detectable color change from yellow to pale red in absorption, and from green to yellow in emission. The detection limit for Zn2+ was estimated at 48.1 nM, which was below the threshold limit value of Zn2+ in drinking water (46 μM) according to World Health Organization. Moreover, the probe T2 displayed low cytotoxicity and good cell membrane permeability at physiological temperature. The imaging of Zn2+ in living cells and the quantitative determination of Zn2+ levels in the real water samples were successfully demonstrated. This study developed a new receptor toward Zn2+ for the further study on the qualitative and quantitative determination of Zn2+ in the biological system.

Two efficient fluorescence molecules, named 1-(4-trifluoromethylphenyl)-2-(4′-(1,4,5-triphenyl-1H-imidazole-2-yl)-[1,1′-biphenyl]-4-yl)-1H-phenanthro[9,10- d ]imidazole ( PPI-PIM-1 ) and 1-(4-trifluoromethylphenyl)-2-(4′-(2,4,5-triphenyl-1H-imidazole-1-yl)-[1,1′-biphenyl]-4-yl)-1H-phenanthro[9,10- d ]imidazole ( PPI-PIM-2 ) were designed and synthesized, in which the electron-withdrawing trifluoromethyl group was introduced firstly to N1-position benzene of phenanthroimidazole to improve the electron transporting ability and tune the charge transfer (CT) component. In addition, compared to biphenanthroimidazole derivatives, here, we break one rigid plane of phenanthroimidazole to inhibit aggregation-induced-quenching (ACQ) and change the position from C1 to N1 to restrict the conjugation length simultaneously. The devices based on PPI-PIM-1 and PPI-PIM-2 exhibited stable deep-blue emission with CIE coordinates of (0.15, 0.08) and (0.15, 0.07) and achieved maximum external quantum efficiencies of 4.3% and 4.5% respectively. More importantly, the corresponding exciton utilization efficiencies are as high as 27.0% and 30.3%.

To increase the fluorescence quantum yield of hybrid local and charge-transfer (HLCT) material, we introduce a symmetric linear D- π -A- π -D structure into molecular design and synthesized a new blue emitter, 2,2'-(2′,3′,5′,6'-tetrafluoro-[1,1':4′,1″-terphenyl]-4,4″-diyl)bis(1-(4-( tert -butyl)phenyl)-1 H -phenanthro[9,10- d ]imidazole) ( 4FBTPI ). Organic light-emitting devices employing 4FBTPI as a dopant emitter show good performances, with CIE (Commission Internationale de l’Enclairage) coordinates of (0.15, 0.09), which is very close to NTSC blue light standard (0.14, 0.08), current efficiencies (CE) of 6.03 cd A −1 , external quantum efficiencies of 6.94%. This performance is comparable to those of recently reported state-of-the-art deep-blue materials with CIE y

In this work, we revealed a new approach for the development of efficient violet-blue emitting materials featuring a hybrid local and charge transfer (HLCT) excited state through the incorporation of naphthyl group(s) as a weak n-type π spacer in a donor–π–acceptor (D–π–A) system. The resulting materials (TPINCz and TPIBNCz) show improved intramolecular charge transfer properties and highly efficient violet-blue fluorescence. It is demonstrated that the pattern of the π spacers has significant influence on the photophysical properties. The incorporation of a naphthyl/binaphthyl spacer between the donor and acceptor moieties can alleviate the common dilemma that enhancing device performance by increasing the charge transfer excited properties often leads to red-shifted emissions. A device using TPINCz as an emissive dopant shows a violet-blue emission with CIE coordinates of (0.153, 0.059) and a record high EQE of 6.56 ± 0.11% at a brightness of 1000 cd m−2. To the best of our knowledge, this performance is the highest among the reported devices with CIEy ≤0.08. Our study provides a new pathway for the design of high-performance violet-blue emitters with a D–π–A architecture in organic electroluminescence applications.

A new fluorescent probe T1, which contained a coumarin fluorophore with a triazole substituted 8-hydroxyquinoline (8-HQ) receptor and a Schiff base spacer, was rationally designed and synthesized. It displayed a high affinity towards Pb2+ ions with a dissociation constant (Kd) of 0.1 μM and possessed a high selectivity for Pb2+ ions. A visually detectable colour change from colourless to yellow and a 30-fold fluorescence enhancement were observed upon addition of Pb2+. Experiments also indicated that a 1 : 1 stoichiometry of T1 with Pb2+ inhibited the photo-induced electron transfer (PET) process, resulting in the increase of fluorescence intensity.

A series of phenanthroimidazole derivatives with N-1 and C-2 position modification have been synthesized, characterized and applied as non-doped emitters in organic light-emitting devices (OLEDs). The compounds show high fluorescence quantum yields high up to 87.51% in solid powder state as well as good thermal and film-forming properties. Crystal structures of 2N-PI, 1N-BPI and 2N-API were determined by X-ray crystallography. Correlations between optoelectronic properties, energy levels and molecular structures of the materials were investigated. It was found that the fluorescence properties of the materials were related to the dihedral angles and moiety replacement position. N-1-imidazole modification (e.g.: 2N-API) favours deep-blue emission, although with a relatively lower quantum yield, it shows comparable device efficiency towards the C-2-imidazole derivative (e.g.: 2N-BPI).

In this paper, a novel quinoline derivative: 8-(pyridin-2-ylmethoxy)quinoline-2-carboxylic acid (Q) has been successfully synthesized, then it was coupled with carbon dots (CDs) to synthesize a CDs–Q nanocomposite by a simple and green method. The CDs–Q nanocomposite can act as a “turn-off” fluorescent chemosensor for detection of Cu2+ ions. It's a good candidate for Cu2+ sensing on account of its excellent properties such as its high sensitivity and selectivity, easy synthesis, excellent fluorescence stability towards temperature and pH, direct detection in aqueous solution and tap water and distinct fluorescence quenching towards Cu2+. We have also discussed the fluorescence quenching mechanism of CDs–Q and the possible coordination mode of CDs–Q with Cu2+. CDs–Q have a wide linear range (0.01–1.2 μM) and high sensitivity towards Cu2+ ions with a detection limit of 0.56 nM. In addition, this fluorescent chemosensor was also applied to determine Cu2+ in tap water with satisfying results.

In this study, by coupling benzothiazole and spiropyrans, three fluorescent probes HBT-pH 1, HBT-pH 2, and HBT-pH 3 were developed for pH variation monitoring. All these probes exhibited remarkable changes of absorption and emission accompanying its protonation under acidic conditions. HBT-pH 1 exhibited OFF-ON response when pH value was changed from 12.00 to 2.02, whereas ratiometric responses (large Stokes shifts) were obtained for HBT-pH 2 and HBT-pH 3. The response was attributed to the open-loop of spiropyran under acidic conditions, which was confirmed by 1H NMR. The pKa values of 6.57, 4.90, and 3.95 were obtained for HBT-pH 1, HBT-pH 2, and HBT-pH 3, respectively, indicating they were suitable for pH variation monitoring. Furthermore, low cytotoxicity and cell imaging of pH changes with HBT-pH 2 in living cells were successfully demonstrated, suggesting potential application in early diagnosis of pH-related diseases.

Efficient deep-blue fluorescent emitters are of particular significance in organic light-emitting devices (OLEDs). An ambipolar deep-blue emitter, 4,4′-bis(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-1,1′-binaphthalene (2NBTPI), was designed, synthesized and applied in a high-efficiency deep-blue emitting OLED. By modifying with binaphthyl, 2NBTPI exhibits a high thermal stability, deep blue emission as well as spatially separated HOMO and LUMO orbits. Comparing with its mononaphthyl counterpart 1,4-bis(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)naphthalene (NBTPI), 2NBTPI shows more balanced charge transport properties, better color purity (color index: (0.15, 0.09) versus (0.15, 0.11)), higher external quantum efficiency (EQE) (5.95% versus 5.73%) and slower efficiency roll-off (EQE roll-off at 100 mA cm−2: 13.1% versus 27.6%). To the best of our knowledge, OLED performances of 2NBTPI are comparable to the best reported non-doped deep-blue emitters.

In this paper, an efficient violet-blue emitter 4,4′′-bis(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazol-2-yl)-1,1′:3′,1′′-terphenyl (m-BBTPI) was designed and synthesized by linking two phenanthroimidazole units via the meta position of a freely rotatable phenyl bridge. The present design provides a suitable level of conjugation between the two phenanthroimidazole units such that fluorescence is strengthened over the single unit while a violet-blue emission can be maintained by limiting the amount of redshift. The new emitter m-BBTPI is also found to have good thermal stability, strong violet-blue emission and bipolar charge transporting properties. An electroluminescent device using m-BBTPI as a non-doped emission layer shows a low turn-on voltage (3.2 V), good colour purity (0.16, 0.06) as well as high current and power efficiencies (1.99 cd A−1, 1.81 lm W−1). These performance parameters are comparable to the state-of-the-art non-doped violet-blue OLEDs.

We report 3-(4,5-diphenyl-1H-imidazol-2-yl)naphthalen-2-ol (DPIN) as an interesting luminescent material displaying ESIPT with a large Stokes shift of ∼180 nm even in protic/polar solvents. Stable homo-dispersed nanoparticles formed by inter- and intramolecular H-bonds in aqueous media and the corresponding aggregation induced enhanced emission with a high quantum yield up to 0.45 were observed. Factors such as pH value and ions (cations and anions) showed a negligible effect on the fluorescence performance. A probe of 3-(4,5-diphenyl-1H-imidazol-2-yl)naphthalen-2-yl-acrylate (DPIN-A) based on this molecule was designed. The results revealed that it can be used for sensing of Cys with high selectivity and sensitivity.

A series of bipolar phenanthroimidazole derivatives, TTP-TPI, DPT-TPI, and DPF-TPI, were designed and synthesized by incorporating polyaromatic hydrocarbon groups to phenanthroimidazole through a phenyl bridge. The bulky polyaromatic hydrocarbon units endow the molecules with high glass-transition temperatures, nonplanar twisty structures which reduce molecular aggregations. The bipolar transporting natures of these materials are demonstrated by single-carrier devices with supported of theoretical calculations. Nondoped organic light-emitting devices (OLEDs) using these phenanthroimidazole derivatives as emitters show blue-violet to sky-blue emissions with Commission Internationale de l’Eclairage (CIE) coordinates of (0.16, 0.05) for TTP-TPI, (0.16, 0.07) for DPT-TPI, and (0.17, 0.24) for DPF-TPI. The TTP-TPI-, DPT-TPI-, and DPF-TPI-based nondoped devices show impressive external quantum efficiencies (EQE) of 5.02, 5.25, 4.85%, respectively (corresponding current efficiencies: 2.10, 3.13, and 8.41 cd/A). ...

Cationic porphyrins are potential antiprion drugs; however, the action mechanisms remain poorly understood. Herein, the interaction between a cationic porphyrin and recombinant human prion protein (rPrP C ) was comprehensively studied by using surface plasmon resonance (SPR), fluorescence, resonance light scattering (RLS), and circular dichroism (CD) spectroscopy. The experimental results showed that the interaction between the cationic porphyrin and rPrP C was pH dependent. The equilibrium association constants obtained from SPR spectroscopy were 4.12 × 10 3 M − 1 at pH 4.0, 1.74 × 10 5 M − 1 at pH 6.0, and 5.98 × 10 5 M − 1 at pH 7.0. The binding constants at 298 K obtained from the fluorescence quenching method were 7.286 × 10 4 M − 1 at pH 4.0 and 1.45 7 × 10 5 M − 1 at pH 6.0. The thermodynamic parameters such as enthalpy change, entropy change, and free energy change were calculated, and the results indicated hydrogen bonds and van der Waals interactions played a major role in the binding reaction. The RLS experiment was performed to study the influence of porphyrin on the rPrP C aggregation at different pH values. The CD experiments were conducted to investigate the effects of porphyrin on the secondary structure and thermal stability of rPrP C . Finally, the comparison of SPR measurement and fluorescence quenching measurement was discussed.

A new blue-emitting carbazole derivative, 3,6-dipyrenyl-9-ethylcarbazole (DPEC), has been designed and synthesized for applications in organic light-emitting devices (OLEDs). Undoped DPEC-based OLEDs give a saturated blue electroluminescence with Commission Internationale de L’Eclairage 1931 coordinates of (0.15, 0.18), and possess high luminous efficiency of 4.75 cd A −1 . On the other hand, DPEC can also function as a hole-transporting layer (HTL). In particular, by replacing N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (NPB) as HTL, a simplified bilayer device demonstrated good performance, comparable to that of the trilayer device. This good device performance illustrates that DPEC is a promising candidate as a blue hole-transporting emitter.

Two highly fluorescent triphenylamines (TPA) end-capped respectively with one and three pyrene arms, namely N,N-diphenyl-4-(pyren-1-yl)aniline (PyTPA) and 4,4′,4′′-trispyrenylphenylamine (TPyPA), have been designed, synthesized and applied as hole-transporting emitters in organic light-emitting devices (OLEDs). While the two compounds have similar chemical structures (the only difference being the number of pyrene arms), devices based on them show distinct electroluminescent characteristics. PyTPA-based devices exhibit intense deep-blue emission with Commission Internationale de L'Eclairage coordinates (CIE) of (0.14, 0.11); whilst TPyPA-based devices emit white light with CIE of (0.31, 0.35). It is considered that the three electron-donating pyrene arms in TPyPA increase its electron-donating ability, which facilitates exciplex formation with the electron-transporter. This gives rise to a yellow exciplex emission and thus shifts the electroluminescence from deep-blue to white. More importantly, both devices can operate at record-low driving voltages (

Deep blue emitters with high quantum yield, good stability, and multifunctionality are still the key technology for white organic light-emitting diodes (WOLEDs). To address this, two multifunctional deep-blue materials 4-{2-[4′-(1,4,5-triphenyl-4,5-dihydro-1H-imidazol-2-yl)-biphenyl-4-yl]-3a,11b-dihydro-phenanthro[9,10-d]imidazol-1-yl}-benzonitrile (CPD) and 4-(2-{4′-[1-(4-tert-butyl-phenyl)-4,5-diphenyl-4,5-dihydro-1H-imidazol-2-yl]-biphenyl-4-yl}-3a,11b-dihydro-phenanthro[9,10-d]imidazol-1-yl)-benzonitrile (tCPD) based on phenanthroimidazole units are designed, synthesized, and characterized. Both the materials show high quantum yields and good stabilities. The deep-blue fluorescent devices using CPD and tCPD as emitters show maximum external quantum efficiency (EQE) of 5.80% and 4.71% along with Commission Internationale de I'Eclairage (CIE) coordinates of (0.15, 0.07) and (0.15, 0.09), respectively. Two-color based WOLEDs are demonstrated by doping Ir(MDQ)2acac into CPD and tCPD with a low doping concentration, both devices show high EQEs of 16.4% and 16.6% and CIEs of (0.49, 0.34) and (0.48, 0.32), respectively. Furthermore, three-color based fluorescence/phosphorescence-WOLEDs (F/P-WOLEDs), with reasonable exciton management, are fabricated to enhance exciton utilization and improve device performance. CPD-based WOLED shows high efficiencies of 49.4 cd A−1, 53.5 lm W−1, 19.0%, and CIE coordinate of (0.46, 0.46). With the same structure, tCPD-based device also shows high efficiencies of 40.6 cd A−1, 47.2 lm W−1, 19.4% along with CIE coordinate of (0.43, 0.45). These results are among the best of reported deep-blue OLEDs and F/P-WOLEDs.

A new blue light-emitting fluorene derivative 2,7-di[8-(7,10-diphenylfluoranthenyl)]-9,9-dimethylfluorene (DFDF) with good thermal stability at 420 °C has been synthesized and characterized. An organic light-emitting device (OLED) with the structure of ITO/NPB (70 nm)/DFDF (30 nm)/TPBI (20 nm)/LiF (0.5 nm)/Al (100 nm) has been investigated, where DFDF serves as a nondoped host emitter. Such a device possesses high current and power efficiencies of 3.8 cd/A and 2.6 lm/W, respectively, and stable bright blue-light emission at λ = 474 nm with Commission Internationale de L’Eclairage coordinates of (0.16, 0.23) over a wide range of operating voltages. The present results verify that DFDF is a promising candidate for a fluorescent blue-light-emitting OLED.

In this paper, a new coumarin-based fluorescent probe for hydrazine was rationally designed and successfully synthesized based on the Gabriel reaction. This novel probe enabled highly sensitive and selective detection of hydrazine. The detection limit was 43.6 nM (1.49 ppb). It displayed distinct changes in the intensity of both absorption and emission spectra upon the addition of hydrazine and remarkable color changes can be visually observed. The sensing mechanism of this probe toward hydrazine was characterized by 1H NMR and mass spectroscopy. Moreover, with the help of theoretical calculations, the sensing capability of this probe for hydrazine detection was described: the electron structure was modulated by a three-substituted group of coumarin once upon the addition of hydrazine. In addition, a test paper experiment indicated its great potential in environment monitoring.

Treatment of 2-phenylpyridines with amino(1,3,2-dioxaborolan-2-yl)diphenylsilane produced fluorosilylated 2-phenylpyridines in good to excellent yields under palladium catalysis. This reaction is the first example of C-H fluorosilylation. Single-crystal X-ray structure analysis revealed a Lewis acid-base interaction between the silicon and nitrogen atoms, and the obtained fluorosilylated products are silafluorene equivalents. The fluorosilylated products showed stronger fluorescence than the corresponding silafluorene derivative.

A phenanthroxazole-based fluorescent sensor for Cd(2+) has been developed. Of particular significance is the specific ratiometric response of the sensor toward Cd(2+) without interference from other biologically important metal ions including Zn(2+). The test paper made of this sensor exhibits both absorption and fluorescent color changes when exposed to Cd(2+) aqueous solution.

A new triphenylamine-bridged fluoranthene derivative, 4-(7,10-diphenylfluoranthen-8-yl)-N-[4-(7,10-diphenylfluoranthen-8-yl)phenyl]-N-phenylaniline (BDPFPA), with a high glass transition temperature of 220 °C has been synthesized and characterized. BDPFPA is a highly fluorescent and versatile material that can be used as a nondoped green emitter and as a hole transporter. BDPFPA was used in a standard trilayer device as the emitting layer, which showed a low turn-on voltage (

A novel fluorescent sensor 2-MZ has been developed. It could simultaneously and selectively detect Zn2+ and Cd2+ in aqueous media. The distinct absorption and fluorescence color changes could be observed by the naked eye. Live cells imaging also demonstrated its potential application in biological systems.

Herein we report the first example of a difluoroboron dibenzoyl based fluorescent probe for Cd(2+) detection. The probe displays high selectivity and sensitivity toward Cd(2+) over Zn(2+) in aqueous solution under physiological conditions. Fluorescence imaging experiments demonstrate its potential application for detecting Cd(2+) in living cells.

A series of phenanthroimidazole derivatives have been synthesized, characterized and applied as non-doped emitters in organic light-emitting devices. The compounds show high fluorescent quantum yields up to 0.75 as well as good thermal and film-forming abilities. Crystal structures of the compounds were determined by X-ray crystallography. Correlations between optoelectronic properties, energy levels and molecular structures of the materials were investigated. It was found that introduction of a thiophene ring on the C2-position of phenanthroimidazole can effectively decrease the ionization potentials (Ip) of the compounds. Fluorescent properties of the materials were found to be related to the dihedral angles in the compounds with different substituents. The low Ip (from 5.00 to 5.21 eV) of the materials enables efficient hole-injection from the hole-transporting layer and results in low turn-on (

An efficient nondoped green organic light-emitting device was demonstrated by using a dual-functional electroluminescent material, 4,4′,4″-tris[8-(7,10-diphenylfluoranthenyl)] phenylamine (TDPFPA). TDPFPA was shown to be a good hole transporting [with a mobility of (1.1–1.2)×10−4cm2V−1s−1 at (1.8–5.6)×105Vcm−1] and efficient fluorescent material with an exceptionally high glass transition temperature of 237°C. The device with a simple structure of indium tin oxide/TDPFPA/4,7-diphenyl-1,10-phenanthroline/LiF∕Al showed green emission with Commission Internationale de L’Eclairage coordinates of (0.24, 0.54), a current efficiency of 9.9cd∕A, and power efficiency of 10.6lm∕W.