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Three AIEE-active V-shaped fused-biscoumarin derivatives were prepared and their potential for application in OLED was explored.

Two coumarin-triarylimidazole hybrid derivatives having a N,N-diethylamine at 7-position and triaryl-substituted imidazole at 3-position on the coumarin core, 3-(1-(4-(tert-butyl)phenyl)-4,5-diphenyl-1H-imidazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (C-IM-Bu) and 3-(1-(4-cyanophenyl)-4,5-diphenyl-1H-imidazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (C-IM-CN), were successfully synthesized for application in organic-light emitting. Their photophysical and electrochemical properties, thermal stability and electroluminescent properties were investigated. The results showed that these compounds have excellent thermal stability, and exhibit strong blue-green emission in dichloromethane solution and green emission in thin solid films. Further, the solution-processed doped devices based on the compounds were fabricated, in which the devices fabricated from C-IM-CN exhibited the best device performance with a turn-on voltage of 3.6 V, a maximum brightness of 6896 cd/m2, a maximum current efficiency of 6.39 cd/A and a maximum external quantum efficiency of 2.92%.

Three new functionalized V-shaped bis-coumarin derivatives were synthesized for OLED applications.

Deep Reinforcement Learning (DRL) has been increasingly attempted in assisting clinicians for real-time treatment of sepsis. While a value function quantifies the performance of policies in such decision-making processes, most value-based DRL algorithms cannot evaluate the target value function precisely and are not as safe as clinical experts. In this study, we propose a Weighted Dueling Double Deep Q-Network with embedded human Expertise (WD3QNE) that incorporates a target Q value function with adaptive dynamic weight for enhanced policy improvement and human expertise in decision-making for sepsis treatment. In addition, the random forest algorithm is employed for feature selection to improve model interpretability. We test our algorithm against state-of-the-art value function methods in terms of expected return, survival rate and action distribution. The results demonstrate that WD3QNE obtains the highest survival rate of 97.81%. Our proposed method is capable of providing reliable treatment decisions with embedded clinician expertise.

Three 2,7,12-trisubstituted triazatruxene derivatives containing different imidazole derived moieties, 5,10,15-tributyl-2,7,12-tris(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d] imidazol-2-yl)phenyl)-10,15-dihydro-5H-diindolo[3,2-a:3′,2′-c]carbazole (2,7,12-TPI-TAT), 5,10,15-tributyl-2,7,12-tris(4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl)-10,15-dihydro-5H-diindolo[3,2-a:3′,2′-c]carbazole (2,7,12-TBI-TAT) and 5,10,15-tributyl-2,7,12-tris(4-(1-(4-(tert-butyl)phenyl)-4,5-diphenyl-1H-imidazol-2-yl)phenyl)-10,15-dihydro-5H-diindolo[3,2-a:3′,2′-c]carbazole (2,7,12-TIM-TAT), were synthesized by grafting different imidazole derived moieties with different electron-withdrawing abilities onto the 2-, 7- and 12-positions of a triazatruxene (TAT) core. A combination of thermal, photophysical and electrochemical characterization studies of these compounds was conducted to investigate the influence of different imidazole derived moieties on the optoelectronic properties of the compounds. Furthermore, solution-processed doped and nondoped devices based on the compounds were fabricated, in which the doped device of 2,7,12-TPI-TAT exhibited the best device performances, while the nondoped device of 2,7,12-TBI-TAT showed the best device performances.

Two new cyanopyridinone-capped 9,9′-bifluorenylidene derivatives, 5,5′,5′′,5′′′-(([9,9′-bifluorenylidene]-3,3′,6,6′-tetrayltetrakis(4-hexylthiophene-5,2-diyl))tetrakis(methanylylidene)) tetrakis(1-butyl-4-methyl-2,6-dioxo-1,2,5,6-tetrahydropyridine-3-carbonitrile) (A1) and 5,5′,5′′,5′′′-(([9,9′-bifluorenylidene]-2,2′,7,7′-tetrayltetrakis(4-octylthiophene-5,2-diyl))tetrakis (methanylylidene))tetrakis(1-(2-ethylhexyl)-4-methyl-2,6-dioxo-1,2,5,6-tetrahydropyridine-3-carbonitrile) (A2), were synthesized as non-fullerene small molecular acceptors for organic solar cells. The compounds exhibited excellent solubility in a variety of common organic solvents such as dichloromethane, toluene and o-dichlorobenzene due to possessing different length alkyl chains on the thiophene-bridged groups and the cyanopyridinone units. The introduction of the strong electron-withdrawing cyanopyridinone groups as the capping groups can improve the intramolecular charge transfer (ICT) and thus broaden the absorption spectra of the molecules. By changing the connection points of the capping groups in the 9,9′-bifluorenylidene core, the photophysical and electrochemical properties of the compounds can be easily adjusted. The photovoltaic performance of A1 and A2 as acceptors was investigated by fabricating solar cells with the following structure: ITO/PEDOT:PSS/PBDB-T:A1(or A2)/PDTNO/Al. The results showed that power conversion efficiencies (PCEs) of 1.01% and 1.98% were obtained using A1 and A2, respectively, as the acceptors without any treatment. After treating the active layers with solvent vapor annealing, their PCEs were increased to 1.28% and 2.94%, respectively.

Two new green-emitting iridium(III) complexes containing styrene-modified phenylpyridine ligands, namely, Ir(ppy-VB)2(acac) (Ir-A) and Ir(ppy-VB)2(Stpip) (Ir-S), where ppy-VB = 2-(4-(((4-vinylbenzyl)oxy)methyl)phenyl)pyridine, acac = acetylacetone, and Stpip = bis(diphenylphorothioyl)amide, have been synthesized and characterized via NMR (1H and 13C) and MS spectroscopy, and the structure of Ir-A has been characterized via single crystal X-ray diffraction. Their photophysical and electrochemical properties and thermal stability were investigated systematically. The results showed that these complexes exhibited green emission, suitable HOMO and LUMO energy levels and good thermal stability.

Two 2,7-disubstituted spiro[fluorene-9,9′-xanthene] derivatives, 2,7-bis(4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl)spiro[fluorene-9,9′-xanthene] (SFX-2BI) and 2,7-bis(4-(1-(4-(tert-butyl)phenyl)-4,5-diphenyl-1H-imidazol-2-yl)phenyl)spiro[fluorene-9,9′-xanthene] (SFX-2IM), were synthesized by grafting imidazole-derived moieties with different electron-withdrawing abilities onto the 2- and 7-positions of a spiro[fluorene-9,9′-xanthene] (SFX) core. Their photophysical and electrochemical properties, thermal stability and electroluminescent properties were investigated. The results showed that these compounds have excellent thermal stability and exhibit strong deep-blue emission in dichloromethane solution. In addition, the vacuum-processed doped and non-doped devices based on SFX-2BI and SFX-2IM were fabricated, in which the device prepared using SFX-2BI as the emitting material exhibited the best device performance with a turn-on voltage of 5.5 V, a maximum brightness of 3984 cd m−2, a maximum current efficiency of 3.65 cd A−1 and a maximum external quantum efficiency of 2.61%.

Two cross-linkable iridium(III) complexes, Ir(L)2(acac) and Ir(L)2(Stpip), where L = 1-phenyl-2-(4′-vinyl-[1,1′-biphenyl]-4-yl)-1H-benzo[d]imidazole, acac = acetylacetonate, and Stpip = bis(diphenylphorothioyl)amide, were synthesized and characterized by elemental analysis, NMR (1H and 13C) spectroscopy and HRMS. The iridium(III) complexes exhibited excellent thermal stability and green–yellow emission with a maximum main peak at 563 nm. The photoluminescence quantum yields of Ir(L)2(acac) and Ir(L)2(Stpip) were 2.77% and 1.80%, respectively, in CH2Cl2 solution. The vacuum-processed electroluminescence device fabricated from Ir(L)2(acac) at 4 wt% doping concentration exhibited a maximum current efficiency (CEmax) of 26.3 cd A−1, a maximum brightness of 9645 cd m−2 and a maximum external quantum efficiency (EQEmax) of 14.7%. The solution-processed electroluminescence device based on Ir(L)2(acac) exhibited a maximum current efficiency (CEmax) of 3.71 cd A−1, a maximum brightness of 2237 cd m−2 and a maximum external quantum efficiency (EQEmax) of 1.36%.

BACKGROUND Internet hospitals are developing rapidly in China, and their convenient and efficient medical services are recognized by more and more patients. How to carry out SDM between doctors and patients in internet hospital diagnosis and treatment services and improve patients' medical experience is a way to further improve online medical service. OBJECTIVE To study the strategy of implementing doctor-patient SDM in internet hospital diagnosis and treatment services based on patients’ needs. METHODS The chi-square test is used to analyze the patient characteristics and medical service needs of internet hospital patients, so as to determine the needs for SDM between doctors and patients of internet hospitals. RESULTS Internet hospital patients from 10 clinical departments are significantly different in gender (χ2value 3424.34, P value 0), age (χ2 value 27.75.81, P value 0), mode of payment (χ2 value 3501.1, P value 0), geographical distribution (χ2 value 347.15, P value 0), and duration of illness (χ2 value 2863.3, P value 0). Patient medical needs include prescribing drugs, prescribing examinations, explanation of medical records, instruction in drug use, preparations before hospitalization, further consultation with doctors (unspecified purpose), treatment plan consultation, initial diagnosis based on symptoms, and follow-up and subsequent consultation after discharge. The medical needs of patients in different clinical departments show significant difference (χ2 value 8465.52, P value 0). CONCLUSIONS Internet hospitals provide a good information platform, and most of the patients admitted by internet hospitals are patients with mild and chronic diseases, which is conducive to SDM between doctors and patients. In the process of implementing doctor-patient SDM, differentiated strategies should be adopted, focusing on patients whose diagnosis, treatment, and follow-up diagnosis are unclear, guiding patients to engage in doctor-patient SDM, and emphasizing the development of doctor-patient SDM assistance tools at the clinical department level and enhancing the policy support and promotion of SDM between doctors and patients at the hospital level.

Background Internet hospitals are developing rapidly in China, and their convenient and efficient medical services are being increasingly recognized by patients. Many hospitals have set up their own internet hospitals to provide web-based medical services. Tianjin Medical University General Hospital has established a multidisciplinary and comprehensive internet hospital to provide diversified medical services according to the needs of patients. A way to further improve web-based medical services is by examining how shared decision-making (SDM) can be carried out in internet hospital diagnosis and treatment services, thereby improving patients’ medical experience. Objective The aim of this study was to analyze the feasibility of implementing doctor-patient SDM in internet hospital diagnosis and treatment services based on patients’ needs in China. Methods In this study, the medical data of 10 representative departments in the internet hospital of Tianjin Medical University General Hospital from January 1 to January 31, 2022, were extracted as a whole; 25,266 cases were selected. After excluding 2056 cases with incomplete information, 23,210 cases were finally included in this study. A chi-square test was performed to analyze the characteristics and medical service needs of internet hospital patients in order to identify the strengths of SDM in internet hospitals. Results The internet hospital patients from 10 clinical departments were significantly different in terms of gender (χ29=3425.6; P Conclusions Our study provides a practical and theoretical basis for the feasibility of doctor-patient SDM in internet hospitals and offers some implementation strategies. We focus on the application of SDM in web-based diagnosis and treatment in internet hospitals rather than on a disease or a disease management software. The medical service needs of different patient groups can be effectively obtained from an internet hospital, which provides the practical conditions for the promotion of doctor-patient SDM. Our findings show that the internet hospital platform expands the scope of SDM and is a new way for the large-scale application of doctor-patient SDM.

Three biscoumarin dyes bridged by polycyclic aromatic bridges (anthracen, pyrene and dibenzo[g,p]chrysene) were prepared as the emissive materials for the application of organic light-emitting devices. The relationship between their structures, photophysical properties, electrochemical properties and performances of organic light-emitting devices are described. The multilayered doped devices with a configuration of ITO/NPB (20 nm)/TBADN: biscoumarin compound (x wt%, 30 nm)/TPBi (30 nm)/Liq (2 nm)/Al (100 nm) have been successfully fabricated by vacuum-deposition method. All the devices showed green emission with high electroluminescent efficiencies. Especially, the device based on the compound containing pyrene as a bridge group at 7% doping concentration showed the best performance with a maximum brightness of 10552 cd/m2, maximum luminous efficiency of 5.39 cd/A and maximum external quantum efficiency (EQE) of 2.35%. Keywords: Biscoumarin derivative, Polycyclic aromatic bridge, Dibenzo[g,p]chrysene, Photoluminescence, Electroluminescence

Two blue donor-acceptor fluorophores with 1,4,5-triphenylimidazole as the electron-transporting unit and phenothiazine as the hole-transporting unit were synthesized by grafting 1,4,5-triphenylimidazole moieties onto 3- and 3,7-position of the phenothiazine core and characterized by spectroscopic methods. Their thermal stability, photophysical, electrochemical and electroluminescence properties were systematically investigated. These compounds exhibit good thermal stability and show blue emission in dichloromethane solution and thin solid films. The solution-processed doped devices were fabricated by using these fluorophores as the emitting dopant in 1,3-bis(N-carbazolyl)benzene host, in which the device fabricated from the fluorophore containing two 1,4,5-triphenylimidazole moieties exhibited blue emission with a luminance of 648 cd/m2 and external quantum efficiency of 1.48%.

Two-dimensional (2D) materials have attracted greatest attention in the past years. In this study, we report 2D conjugated polymeric nanocrystals, polyhedral oligomeric silsesquioxanes (POSS) coval...

Two new coumarin derivatives containing phenothiazine or phenoxazine moiety, 3-(benzo[d]oxazol-2-yl)-7-(10H-phenoxazin-10-yl)coumarin (PXZ-C) and 3-(benzo[d]oxazol-2-yl)-7-(10H-phenothiazin-10-yl)coumarin (PTZ-C), were synthesized and characterized by elemental analysis, NMR spectroscopy, and MS. Their photophysical and electrochemical properties and thermal stabilities were investigated systematically. The results showed that these compounds have good thermal stability. The compound PTZ-C exhibits weak blue–green emission upon ultraviolet light excitation, whereas the compound PXZ-C displays weak blue emission.

Two new N,N-chelated difluoroboron complexes, PIBF2-Cz and PI-BODIPY, containing phenanthroimidazole moiety were synthesized and characterized by elemental analysis, NMR spectroscopy and MS. Their photophysical and electrochemical properties and thermal stabilities were investigated systematically. The results showed that these N,N-chelated difluoroboron complexes not only exhibit excellent thermal stabilities but also emit strong green emissions with photoluminescence quantum efficiency of 95.71% and 67.22% in chloroform solutions. Furthermore, based on these N,N-chelated difluoroboron complexes, the green organic light-emitting devices with a configuration of ITO/NPB (20 nm)/TBADN: difluoroboron complex (x wt%, 30 nm)/TPBi (30 nm)/Liq (2 nm)/Al (100 nm) have been successfully fabricated by vacuum-deposition method, in which the devices fabricated from PIBF2-Cz exhibited the best electroluminescence performance with a maximum brightness of 20290 cd/m2 and a maximum luminous efficiencies of 7.97 cd/A and a maximum external quantum efficiency (EQE) of 1.88%.

Two new cationic iridium(III) complexes were successfully synthesized as highly sensitive and selective phosphorescent sensors for detection of Cu2+ in MeOH/H2O (1:1) solution and in living cells. These cationic Ir(III) complexes were prepared by reactions of two different Ir(III) chloro-bridged dimers with 2,2′-dipyridine tethered DPA (di(2-picolyl)amine) moiety as the ancillary ligand. These phosphorescent sensors displayed significant reversible phosphorescence quenching upon binding to Cu2+ ions with a 10 ppb detection limit. They had strong binding ability with Cu2+ ions and the binding ratios were approximately 1:1, and also exhibited good cell permeability and good imaging characteristics in detecting Cu2+ ions in living cells. It is worth mentioning that one of the phosphorescent sensors is almost nontoxic to Hela cells, indicating that it greatly increases the possibility of application in biochemistry.

A 9,9′-bifluorenylidene derivative, 2,2′,2′′,2′′′-([9,9′-bifluorenylidene]-2,2′,7,7′-tetrayltetrakis(4-octylthiophene-5,2-diyl))tetrakis(methanylylidene)tetrakis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)tetramalononitrile (BF-TDCI4), was synthesized as an electron acceptor for organic photovoltaic cells. Its photophysical and electrochemical properties and thermal stability were investigated systematically. The photovoltaic devices were fabricated using PTB7-Th as the electron donor and BF-TDCI4 as the electron acceptor at various composition ratios. The optimized device exhibited a maximum power conversion efficiency of 4.35% with an open-circuit voltage of 0.87 V.

Three novel fullerene derivatives containing a C60-fluorene core and thiophenyl, terthiophenyl and tetrathiophenyl groups grafted at the 2-position of the fluorene ring, respectively, were synthesized and characterized. Their photophysical and electrochemical properties were investigated systematically. The results showed that their UV-vis absorption bands in the range of 350–500 nm were much wider and stronger than that of the traditional fullerene derivative PC61BM, and the LUMO energy levels of the synthesized fullerene derivatives were gradually up-shifted by increasing of the number of thiophene rings in the oligothiophene units.

A carbazole-functionalized bis-β-diketone as ancillary ligand, 1,1'-(9-(heptan-3-yl)-9H-carbazole-3,6-diyl)bis(4,4,4-trifluorobutane-1,3-dione) (H2L), which contains two trifluorinated alkyl groups, has been prepared for the synthesis of two green and red emitting dinuclear Ir(III) complexes with the general formula Ir2(CˆN)4L [CˆN = 3-(pyridine-2-yl)coumarinato (1L) and 2-(1-naphthyl)benzothiazole (2L)]. The photophysical and electrochemical properties and thermal stabilities of two dinuclear Ir(III) complexes were investigated systematically. The results showed that two dinuclear Ir(III) complexes not only exhibit excellent thermal stabilities, but also emit stronger green and red emissions, respectively. Furthermore, based on two dinuclear Ir(III) complexes, the solution-processed organic light-emitting devices have been successfully fabricated, in which the devices fabricated from the green emissive Ir(III) complex exhibited a maximum brightness of 6057 cd/m2 and a maximum luminous efficiencies of 16.39 cd/A and the devices fabricated from the red emissive Ir(III) complex displayed a maximum brightness of 1949 cd/m2 and a maximum luminous efficiencies of 2.52 cd/A.

Three anthracen- or pyrene-based coumarin derivatives have been successfully synthesized and characterized by EA, IR and 1H NMR. The photophysical properties of all derivatives were investigated by UV-Vis and photoluminescence spectroscopic analysis. Their thermal stabilities were demonstrated by TGA. These compounds exhibit strong blue mission under ultraviolet light excitation and have potential possible to explore organic electroluminescent materials. The vacuum-processed doped devices with a configuration of ITO/TAPC (20 nm)/TBADN: b1 (x wt%, 30 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) was fabricated, in which the devices based on b1 exhibited the best electroluminescence performance with a maximum brightness of 8165 cd/m2 and a maximum luminous efficiencies of 6.13 cd/A and a maximum external quantum efficiency (EQE) of 2.75%.

Three new iridium complexes containing 3-(pyridine-2-yl)coumarin as the cyclometalated ligand (L) and 1-(3,5-bis(trifluoromethyl)phenyl)-3-(4-methoxyphenyl)propane-1,3-dione (1L), 1-(furan-2-yl)-4,4-dimethylpentane-1,3-dione (2L) and 1-(3,4-dimethoxyphenyl)-4,4-dimethylpentane-1,3-dione (3L) as the ancillary ligands, respectively, were synthesized as emissive materials for organic light-emitting devices. Among them, the crystal structure of the Ir(III) complex based on the ancillary ligand 1L was characterized by single crystal X-ray diffraction. The photophysical and electrochemical properties and thermal stabilities of the Ir(III) complexes were systematically investigated. The results showed that all the Ir(III) complexes not only exhibit excellent thermal stabilities but also emit strong green emissions. Furthermore, based on these Ir(III) complexes, solution-processed green organic light-emitting devices with a configuration of ITO/PEDOT:PSS/PVK:PBD (7 : 3, wt%):Ir(III) complex (x wt%, 30 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) have been successfully fabricated, in which the devices fabricated from the Ir(III) complex based on the ancillary ligand 3L exhibited the best electroluminescence performance with a maximum brightness of 9275 cd m−2 and a maximum luminous efficiency of 19.38 cd A−1 and a maximum external quantum efficiency (EQE) of 5.37%.

Herein, three novel 9,9′-bifluorenylidene derivatives containing thiophenyl, terthiophenyl, and tetrathiophenyl groups at the 2- and 2′-positions of the 9,9′-bifluorenylidene skeleton were synthesized and characterized. Their photophysical and electrochemical properties were investigated systematically. The ground state geometries and electronic distributions of the HOMO and LUMO energy levels of the 9,9′-bifluorenylidene derivatives were calculated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at the B3LYP/6-31G(d) level.

Four new phenanthroimidazole/N,N-diphenylnaphthalen-2-amine hybrid compounds, 6-(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazole-2-yl)phenyl)-N,N-bis(4-methoxyphenyl)naphthalen-2-amine (PPI-NPA-OMe), N,N-bis(4-(tert-butyl)phenyl)-6-(4-(1-(4-(tert-butyl) phenyl)-1H-phenanthro[9,10-d]imidazole-2-yl)phenyl)naphthalen-2-amine (PPI-NPA-t-Bu), 6-(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d]imidazole-2-yl)phenyl)-N,N-di-p-tolylnaphthalen-2-amine (PPI-NPA-Me) and 4,4'-((6-(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro[9,10-d] imidazole-2-yl)phenyl)naphthalen-2-yl)azanediyl)dibenzonitrile (PPI-NPA-CN), were successfully synthesized for application in blue light emitting. The thermal stabilities, photophysical and electrochemical properties of the compounds were investigated. Furthermore, the vacuum-processed devices based on these compounds were fabricated, in which the device based on the compound PPI-NPA-OMe exhibited the best electroluminescence performance with a maximum brightness of 12,593 cd/m2, a maximum current efficiency of 9.23 cd/A and a maximum external quantum efficiency (EQE) of 4.92%.

Three new imidazole-derived moiety/spiro[fluorene-9,9′-xanthene] hybrid compounds, 1-phenyl-2-(4-(spiro[fluorene-9,9′-xanthen]-2-yl)phenyl)-1H-benzo[d]imidazole (SFX-PBI), 1-(4-(tert-butyl)phenyl)-2-(4-(spiro[fluorene-9,9′-xanthen]-2-yl)phenyl)-1H-phenanthro[9,10-d]imidazole (SFX-PPI), and 1-(4-(tert-butyl)phenyl)-4,5-diphenyl-2-(4-(spiro[fluorene-9,9′-xanthen]-2-yl)phenyl)-1H-imidazole (SFX-PIM), were successfully synthesized for highly efficient blue light-emitting devices. The thermal stabilities, photophysical and electrochemical properties of the hybrid compounds were investigated. These hybrid compounds exhibited strong deep blue emission in solutions. Furthermore, the vacuum-processed nondoped devices based on these compounds were fabricated, in which the device based on the compound SFX-PPI exhibited the best electroluminescence performance with a maximum brightness of 4542 cd/m2, a maximum current efficiency of 4.51 cd/A and a maximum external quantum efficiency (EQE) of 5.03%.

A new Cu(II) selective phosphorescent sensor based on a cationic iridium(III) complex was synthesized and characterized. Compared with other commonly coexisting metal ions, the Ir(III) complex displayed significant phosphorescence quenching for detecting Cu2+ with a 1:1 stoichiometry in MeOH/H2O (1:1, v/v) solution. Upon addition of Cu2+, the rapid quenching of emission intensity provided a sensitive method for detection of Cu2+. The corresponding detection limit was determined to be 7.6 × 10−8 M and the association constant between the Ir(III) complex and Cu2+ was calculated to be 0.31 × 105 M−1. Luminescence imaging experiments demonstrated that this Ir(III) complex was cell permeable and suitable for monitoring intracellular Cu2+ in living Hela cells by confocal microscopy.

Two novel cationic Ir(III) complexes, [(nbt)2Ir(L)](PF6) and [(CF3-bt)2Ir(L)](PF6), where nbt = 2-(1-naphthyl)benzothiazole; CF3-bt = 2-phenyl-6-(trifluoromethyl)-benzothiazole and L = 1-(4-(tert-butyl)phenyl)-2-(5-(9-(p-tolyl)-9H-carbazol-3-yl)pyridin-2-yl)-1H-phenanthro [9,10-d]imidazole, were successfully synthesized and characterized. The structures of L and [(nbt)2Ir(L)](PF6) were confirmed by single crystal X-ray diffraction. Their photophysical, electrochemical properties and thermal stabilities were investigated systematically. The results showed that the Ir(III) complexes had higher thermal stabilities, and exhibited strong red emission and orange emission, respectively.

Four new carbazole-based coumarin derivatives comprising a carbazole core and one or two coumarin chromophores, 7-(diethylamino)-3-(4-(9-(p-tolyl)-9H-carbazol-3-yl)phenyl)coumarin (Cz-Ph-C) and 3,3'-((9-(p-tolyl)-9H-carbazole-3,6-diyl)bis(4,4′-phenyl))bis(7- (diethylamino)coumarin) (Cz-2(Ph-C)), 7-(diethylamino)-3-(5-(9-(p-tolyl)-9H-carbazol-3- yl)thiophen-2-yl)coumarin (Cz-Th-C) and 3,3'-((9-(p-tolyl)-9H-carbazole-3,6-diyl)bis(thiophene- 5,2-diyl))bis(7-(diethylamino)coumarin) (Cz-2(Th-C)), were successfully synthesized as the emissive materials for organic light-emitting devices. The photophysical, electrochemical properties and thermal stabilities of the compounds were systematically investigated. The results showed that these coumarin-carbazole hybrids exhibited excellent thermal stabilities and high photoluminescence quantum efficiencies in dichloromethane solutions, and they emitted strong green emissions. The vacuum-processed doped devices with a configuration of ITO/TAPC (20 nm)/TBADN: Coumarin-carbazole hybrid (x wt%, 30 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) was fabricated, in which the devices based on Cz-Ph-C exhibited the best electroluminescence performance with a maximum brightness of 12910 cd/m2 and a maximum luminous efficiencies of 7.39 cd/A and a maximum external quantum efficiency (EQE) of 3.36%.

A novel N-coumarin derivative, namely 9,10-[di-p-(7-diethylamino-coumarin-3-yl) thiopheneyl]anthracene ((CTh)2A), containing anthracene as the core and 3-thiophene N-coumarin as the substituent was...

Three new coumarin derivatives containing biphenyl group have been successfully synthesized and characterized by EA, IR and NMR. The photophysical properties of all derivatives were investigated by UV–vis and photoluminescence spectroscopic analysis. Their thermal stabilities were demonstrated by TGA. The doped light-emitting devices using the coumarin derivatives as dopants were fabricated. The results show that one of coumarin derivatives with coumarin-biphenyl skeleton would serve as promising luminescent materials.

One new phosphorescent polyhedral oligomeric silsesquioxane (POSS) material consisting of one red emissive Ir(III) complex unit and seven carbazole moieties covalently attached to a POSS core was successfully synthesized and characterized. The phosphorescent POSS material had good thermal stability due to the significant effect of the POSS core, and its photoluminescence and electroluminescence performances were improved because the POSS core reduced interactions among the emissive units and diminished concentration quenching. Solution processed light-emitting device based on the POSS material showed a maximum current efficiency of 4.33 cd/A with Commission Internationale de LʹEclairage (CIE) coordinates of (0.67, 0.28).

Two new green-emitting Ir(III) complexes containing a hole transporting group-functionalized benzimidazole ligand (L) as the cyclometalated ligand, and acetylacetonate and picolinate as the ancillary ligands, Ir(L)2(acac) and Ir(L)2(pic), where L = 1-(4-(9H-carbazole-9-yl)phenyl)methyl-2-(4-(9H-carbazol-9-yl)phenyl)-1H-benzimidazole, were successfully synthesized for use as green phosphorescent organic light-emitting diodes. The photophysical and electrochemical properties and thermal stabilities of the Ir(III) complexes were systematically investigated. The results showed that the Ir(III) complexes had high thermal stabilities and strong green emissions, and the ancillary ligand pic induced a blue shift of 10 nm in comparison with the Ir(L)2(acac) complex (517 nm). Solution processed light-emitting devices based on the Ir(L)2(acac) complex exhibit a maximum efficiency of 12.57 cd A−1 and a maximum brightness of 4914 cd m−2, while devices based on Ir(L)2(pic) display a maximum efficiency of 6.73 cd A−1 and a maximum brightness of 3690 cd m−2.

Two carbazole-substituted fullerene derivatives containing mono- and bi-C60 units, (9-butyl-9H-carbazole-3-yl)-C61-butyric acid methyl ester (Cz-C60) and (9-butyl-9H-carbazole-3,6-diyl)-bis(C61-butyric acid methyl ester) (Cz-2C60), were successfully synthesized and characterized by NMR, MS and FT-IR spectroscopy. The photophysical, electrochemical properties and thermal stabilities of the fullerene derivatives were systematically investigated. P3HT-based organic photovoltaic devices were fabricated using Cz-C60 and Cz-2C60 as electron acceptors. The highest power conversion efficiencies (PCEs) of the devices fabricated with Cz-C60 and Cz-2C60 were 3.88 and 3.59%, respectively.

Two benzo[d]imidazole/triazatruxene hybrid compounds, 5,10,15-tributyl-2,7,12-tris(4-(1-phenyl-1H-benzo[d]imidazole-2-yl)phenyl)-10,15-dihydro-5H-diindolo[3,2-a:3′,2′-c]carbazole (2,7,12-TBI-TAT) and 5,10,15-tributyl-3,8,13-tris(4-(1-phenyl-1H-benzo[d]imidazole-2-yl)phenyl)-10,15-dihydro-5H-diindolo[3,2-a:3′,2′-c]carbazole (3,8,13-TBI-TAT), were synthesized by the introduction of three benzo[d]imidazole (BI) moieties at 2-, 7-, 12-positions and 3-, 8-, 13-positions of the alkylated triazatruxene (TAT) core, respectively. Their thermal stabilities, photophysical and electrochemical properties were systematically investigated. These hybrid compounds exhibited good solubility as well as excellent thermal stability. Besides, the solution-processed doped and non-doped OLEDs based on the compounds were fabricated, in which the non-doped device fabricated from 2,7,12-TBI-TAT exhibited the best electroluminescence performance with a maximum brightness of 10075 cd/m2, a maximum current efficiency of 5.35 cd/A and a maximum external quantum efficiency (EQE) of 2.25%.

Four new indolo [3,2-b]carbazole derivatives containing imidazole-derived moieties, 2,8-bis(4-(9-(4-(tert-butyl)phenyl)-9H-pyreno [4,5-d]imidazol-10-yl)phenyl)-5,11-bis(2-ethylhexyl)-5,11-dihydroindolo [3,2-b]carbazole (Py-ICZ-Py), 2,8-bis(4-(1-(4-(tert-butyl)phenyl)-1H-phenanthro [9,10-d]imidazol-2-yl)phenyl)-5,11-bis(2-ethylhexyl)-5,11-dihydroindolo [3,2-b]carbazole (PI-ICZ-PI), 5,11-bis(2-ethylhexyl)-2,8-bis(4-(1-phenyl-1H-benzo [d]imidazol-2-yl)phenyl)-5,11-dihydroindolo [3,2-b]carbazole (BI-ICZ-BI) and 2,8-bis(4-(1-(4-(tert-butyl)phenyl)-4,5-diphenyl-1H-imidazol-2-yl)phenyl)-5,11-bis(2-ethylhexyl)-5,11-dihydroindolo [3,2-b]carbazole (IM-ICZ-IM), were successfully synthesized for highly efficient blue light-emitting devices. The thermal stabilities, photophysical and electrochemical properties of the hybrid compounds were investigated. These hybrid compounds exhibited strong blue emissions in solutions. Furthermore, the vacuum-processed doped devices based on these compounds were fabricated, in which the devices based on the compound PI-ICZ-PI exhibited the best electroluminescence performance with a maximum brightness of 3973 cd/m2, a maximum current efficiency of 3.67 cd/A and a maximum external quantum efficiency (EQE) of 2.64%.

Two coumarin derivatives based on spiro [fluorene-9,9′-xanthene] (SFX), named SFX-CS and SFX-CD, were successfully synthesized and their optical and electrochemical properties have been characterized. SFX-CS and SFX-CD were fabricated as dopant in TBADN-hosted OLED devices. The results show that SFX-CS exhibits better device efficiencies with maximum brightness of 6995 cd/m2, maximum luminous efficiency of 8.24 cd/A and maximum external quantum efficiency (EQE) of 3.86% at 10% doping concentration.

Two new red-emitting Ir(III) complexes containing 2-(1-naphthyl)benzothiazole as cyclometalated ligands and the carrier transporting group-functionalized picolinate as ancillary ligands have been successfully synthesized and characterized. The Ir(III) complexes have good thermal stability with less than 2% weight-reduction occurring at 285 °C, and exhibit strong red emissions. The doped light-emitting devices using the Ir(III) complexes as dopants were fabricated. The result indicated that the light-emitting devices fabricated by the carbazole-functionalized complex and the diaryl-1,3,4-oxadiazole-functionalized complex exhibited red emissions with a maximum brightness of 3074 and 2520 cd/m2 at 10.7 V and a maximum current efficiency of 4.84 and 5.18 cd/A, respectively.

In this study, a new iridium(III) complex containing coumarin derivative as the cyclometalated ligand (L) and 7-allyl-8-hydroxyquinoline (Hq-allyl) as the ancillary ligand, Ir(III)bis(3-(pyridin-2-yl)coumarinato N,C 4 )(7-allyl-8-hydroxyquinolinolato) [Ir(L) 2 (q-allyl)], was firstly synthesized as the emissive iridium complex. Then a macromolecule consisting of the emissive iridium complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core, 7Cz-Ir(L) 2 (q)-POSS, was successfully synthesized by hydrosilylation reaction in the presence of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane (Pt-dvs) as the catalyst. The macromolecule has good thermal stability due to the significant effect of the POSS core, and its photoluminescence performance is improved because the POSS core reduced interactions among the emissive units and diminished concentration quenching in the solid state.