•DETPCZ and DECZDPE are synthesized by combining phenylethene, carbazole and dimesitylboron moieties.•These compounds exhibit aggregation-induced emission (AIE) properties.•Efficient non-doped electroluminescent devices fabricated with DETPCZ and/or DECZDPE show excellent performances.Two novel phenylethene-carbazole derivatives containing dimesitylboron groups, 3-(dimesitylboryl)-9-ethyl-6-(1,2,2-triphenylvinyl)-9H-carbazole and 1,2-bis(6-(dimesitylboryl)-9-ethyl-9H-carbazol-3-yl)-1,2-diphenylethene are presented. The foregoing mono- and bis-carbazole containing compounds combine the aggregation-induced emission properties of phenylethene and the hole and electron transporting properties of carbazole and dimesitylboron substituents respectively. An extensive investigation of their optical and electrical properties reveals that these aggregation-induced emission active scaffolds exhibit excellent thermal stability (Td up to 254 °C) with high electrochemical stability. Compared to our previous systems, the OLED device using the mono-carbazole derivative as a sky-blue emitter shows improved parameters such as the maximum luminance and maximum luminance efficiency of 13,930 cd m−2 and 4.74 cd A−1, respectively. The device based on the blue–green emitting bis-carbazole derivative features equally high maximum luminance and maximum luminance efficiency of 15,780 cd m−2 and 6.90 cd A−1, respectively.

•Two compounds based on diphenylethene framework were synthesized and characterized by single crystal X-ray diffraction.•They exhibit aggregation-induced emission (AIE) properties.•Efficient multi-layer non-doped electroluminescent devices fabricated with them show good electroluminescent performances.Introducing the hole-transporting carbazole moiety into an aggregation-induced emissive tetraarylethene skeleton and attaching electron-transporting dimesitylboron groups to the periphery, we obtain two novel electroluminescent materials. Their structures are fully characterized by elemental analysis, mass spectrometry, NMR spectroscopy and X-ray crystallography. Furthermore, their thermal, electrochemical, as well as photophysical properties including AIE-behavior are systematically investigated not only by experimental methods but also by DFT computation. Thereby, we show that the two compounds possess high thermal and electrochemical stability with a remarkable AIE-behavior. X-ray crystal analyses aided by DFT calculations provide insights in the origin of the luminescent properties and AIE features. Ultimately, two non-doped OLEDs (Device A and Device B) were fabricated by using PDPBCE and BDPBCE as light-emitting layer, respectively. Device A showed yellowish-green light with a turn-on voltage of 3.8 V, a maximum brightness of 59130 cd m−2 and a maximum current efficiency of 6.43 cd A−1. Device B exhibited greenish-yellow light with a turn-on voltage of 3.0 V, a maximum brightness of 67,500 cd m−2 and a maximum current efficiency of 11.2 cd A−1.

•Two new tetraphenylethene derivatives are synthesized.•They exhibit aggregation induced emission (AIE) properties.•Non-doped electroluminescent devices show good electroluminescent performance.Two novel aggregation-induced emission (AIE)-active luminogens of BDTPE and BBTPE, comprising tetraphenylethene (TPE), dimesitylboron, and diethylamine units, were successfully synthesized. The thermal, photophysical, and electrochemical properties of these compounds were investigated by thermal analysis, UV–vis absorption spectroscopy, fluorescence spectroscopy, theoretical calculation, and electrochemical methods, respectively. The non-doped OLED device (Device M) constructed using BDTPE as the emitting layer exhibits efficient yellow light emission with a maximum current efficiency of 2.87 cd A−1 and a maximum luminance of 1978 cd m−2, while the non-doped OLED device (Device N) based on BBTPE gives yellow emissions and exhibits efficient performance with a maximum current efficiency of 2.92 cd A−1 and a maximum luminance of 5292 cd m−2. The electroluminescence properties of these compounds demonstrate their potential application as yellow AIE fluorophores in OLEDs.

A novel molecule, 3,6-bis(dimesitylboryl)-9-(4-(1,2,2-triphenylvinyl)phenyl)-9H-carbazole (DTPC), was synthesized by introducing two dimesitylboron groups and one tetraphenylethene group to the 3-position, 6-position, and 9-position of carbazole, respectively. The structure of DTPC was fully characterized by proton nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis. The thermal, electrochemical, and photophysical properties of DTPC were studied by thermogravimetry in conjunction with electrochemistry, UV–vis absorption spectroscopy and fluorescence spectroscopy. The results reveal that DTPC has excellent aggregation-induced emission properties. The multilayer electroluminescent device fabricated by using DTPC as light-emitting layer emits the blue light (λmax 489 nm) with CIE coordinates (0.17, 0.29) and shows good electroluminescent performances with the turn-on voltage of 5.7 V, maximum luminance of 5709 cd/m2 (at 15 V) and maximum luminance efficiency of 4.31 cd/A (at 8.2 V).A novel compound based on tetraphenylethene, carbazole and dimesitylboron moieties with aggregation-induced emission (AIE) properties was synthesized and utilized as a highly efficient blue light-emitting material in OLEDs.

A new bipolar host material based on carbazole and dimesitylboron moieties, 3,6-bis(dimesitylboryl)-9-(4-(dimesitylboryl)phenyl) carbazole (BDDPC), has been successfully synthesised and characterised by elemental analysis, nuclear magnetic resonance spectroscopy, mass spectrometry and thermogravimetric analysis. The electrochemical and photophysical properties of BDDPC are studied by both experimental and theoretical methods. BDDPC exhibits excellent thermal stability (Td = 234 °C), electrochemical stability, high fluorescence quantum yield (0.95) and high triplet energy (2.83 eV). A red phosphorescent organic light-emitting diode (PhOLED) device comprising BDDPC as the host material and Os(bpftz)2(PPh2Me)2 as the dopant is fabricated and displays promising electrophosphorescence properties with a turn-on voltage of 3.0 V, a maximum brightness of 12337 cd m−2 and a maximum current efficiency of 11.04 cd A−1. Similarly, BDDPC is used to fabricate a green PhOLED device with Ir(ppy)2(acac) as the dopant, possessing a turn-on voltage of 2.5 V, a maximum brightness of 26473 cd m−2 and a maximum current efficiency of 38.60 cd A−1. Furthermore, a blue PhOLED device with BDDPC as the host material and FIrpic as the dopant is fabricated with a turn-on voltage of 3.0 V, a maximum brightness of 7622 cd m−2 and a maximum current efficiency of 7.39 cd A−1. It is anticipated that BDDPC has great potential in manufacturing PhOLED devices for display or lighting applications.

•We synthesized a novel carbazole derivative containing dimesitylboron groups (DDCPC).•DDCPC exhibits aggregation induced emission (AIE) properties and excellent thermal stability.•Efficient OLEDs fabricated with DDCPC show pure blue emission and good electroluminescent performances.A novel carbazole derivative containing dimesitylboron groups, 3-dimesitylboryl-9-(4-(3-dimesitylborylcarbazolyl)phenyl)carbazole has been successfully synthesized by introducing two dimesitylboron groups (two electron-acceptors) to 3-position and 3′-position of 1, 4-bis(carbazolyl)benzene (an electron-donor), respectively. The structure of the compound was fully characterized by elemental analysis, mass spectrometry and proton nuclear magnetic resonance spectroscopy methods. The electrochemical and photophysical properties of the compound were studied by electrochemical methods, UV–vis absorption spectroscopy and fluorescence spectroscopy. Our results show that the compound exhibits excellent thermal stability (Td = 190 °C) and electrochemical stability as well as aggregation induced emission properties. The multi-layered organic light-emitting diodes device was fabricated by using the compound as non-doped emitter. The device shows good electroluminescent performances with the same blue emission color (λ = 478 nm) at different voltages, a turn-on voltage of 3.8 V, a maximum luminance of 2784 cd/m2 and a maximum luminance efficiency of 3.25 cd/A.A novel carbazole derivative containing dimesitylboron groups with aggregation induced emission properties was synthesized and utilized as a highly efficient blue light-emitting material in OLEDs.

•A novel asymmetric indolo[3,2-b]carbazole compound was synthesized.•The compound contains benzothiazole and diphenylamino moieties.•The compound has strong intramolecular charge transfer character.•The compound can be served as an excellent hole-transporting material in OLEDs.A novel asymmetric donor–π-donor–π-acceptor compound, 2-benzothiazolyl-8-diphenylamino-5,11-dihexylindolo[3,2-b]carbazole (BDDAICZ), has been successfully synthesized by introducing a benzothiazole moiety (as an electron-acceptor) and a diphenylamino moiety (as an electron-donor) to 2-position and 8-position of indolo[3,2-b]carbazole moiety (as a skeleton and an electron-donor), and characterized by elemental analysis, 1H NMR, 13C NMR and MS. The thermal, electrochemical properties of BDDAICZ were characterized by thermogravimetric analysis combined with electrochemistry. The absorption and emission spectra of BDDAICZ was experimentally determined in several solvents and computed using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The calculated absorption and emission wavelengths are coincident with the measured data. The ionization potential (IP), the electron affinity (EA) and reorganization energy of BDDAICZ were also investigated using density functional theory (DFT). Charge-transporting properties of BDDAICZ were characterized by OLEDs devices fabricated by using it as charge-transport layers. The results show that BDDAICZ has excellent thermal stability, electrochemical stability and hole-transporting properties, indicating its potential application as a hole-transporting material in OLEDs devices.Graphical abstract

A novel indolo[3,2-b]carbazole derivative containing B(Mes)2 groups, 5,11-dibutyl-2,8-bis(dimesitylboryl) indolo[3,2-b]carbazole (DBDMBICZ), was synthesized and structurally characterized by elemental analysis, NMR, MS. The thermal, electrochemical and photophysical properties of DBDMBICZ were characterized by thermogravimetric analysis, electrochemical methods, UV–vis absorption spectroscopy and fluorescence spectroscopy. DBDMBICZ exhibited high fluorescence quantum yields (Φmax = 0.76) in solution and excellent thermal stability (Td = 290 °C, Tg = 170 °C) and electrochemical stability. The multi-layered OLEDs devices with the configuration of ITO/NPB/CBP/light-emitting layer/Bphen/LiF/Al are fabricated by using DBDMBICZ as light-emitting layer. The devices show the same pure blue emissions at different voltages and relative good electroluminescent performances. The results indicate that DBDMBICZ has potential applications as an excellent optoelectronic material in optical field.Graphical abstractHighlights► We synthesized a novel dimesitylboron-based indolo[3,2-b]carbazole derivative (DBDMBICZ). ► DBDMBICZ exhibited high fluorescence quantum yields in solution and excellent thermal stability. ► Efficient OLEDs fabricated with DBDMBICZ show pure blue emission and relative good electroluminescent performances.

•A novel asymmetric indolo[3,2-b]carbazole compound.•which incorporate a benzothiazole unit (electron-acceptor) and a dimesitylboron unit (electron-acceptor) to 2- and 8-position of indolo[3,2-b]carbazole (electron-donor) respectively.•was investigated as a highly selective ratiometric fluorescence sensor with remarkable colour changes for fluoride ion.A novel asymmetric acceptor–π-donor–π-acceptor compound, 2-benzothiazolyl-8-dimesitylboryl-5,11-dihexylindolo[3,2-b]carbazole (BDDICZ), has been successfully synthesized by introducing a benzothiazole (electron-acceptor) moiety and a dimesitylboron (electron-acceptor) group to 2-position and 8-position of indolo[3,2-b]carbazole (an electron-donor), respectively. The structure of BDDICZ was fully characterized by NMR, MS and elemental analysis and was studied by both experimental and theoretical methods. Our results demonstrate that BDDICZ is a sensitive ratiometric fluorescence probe which shows remarkable color change with fluoride ion (F−). The theoretical calculations confirm that BDDICZ can readily react with tetrabutylammonium fluoride (Bu4N+F−) to form an adduct of (Bu4N)+(BDDICZ·F)−. Moreover, BDDICZ possesses appropriate HOMO and LUMO energy states and a high fluorescence quantum yield, indicating its potential application as an ideal hole-transporting and/or light-emitting material in optoelectronic devices.

Nanoparticles of a novel boron-based carbazole derivative have been reported. They exhibit efficient green fluorescence, aggregation induced ratiometric fluorescence change and green/blue fluorescent switching to sense VOCs.

A novel boron-containing π-conjugated compound BCCB has been synthesized by the introduction of electron-acceptors (dimesitylboron groups) at the 3,3′-positions of a carbazole dimer (electron-donor). The compound BCCB possesses excellent electrochemical properties and high fluorescence quantum yields. In addition, BCCB is a sensitive fluorescence sensor with remarkable colour changes and the results could be confirmed through theoretical calculations of the compounds BCCB and [nBu4N]+2[BCCB·(F)2]2−. Our studies indicate that BCCB could be used as an excellent optoelectronic material in OLED devices and a ratiometric fluorescent chemosensor.

A novel A-π-D-π-D-π-A type compound, containing two benzothiazole rings as electron acceptors and two N-ethylcarbazole groups as electron donors, (E)-1,2-bis(3-(benzothiazol-2-yl)-9-ethylcarbazol-6-yl)ethene (BBECE), was synthesized and characterized by elemental analysis, NMR, MS and thermogravimetric analysis. Electrochemical property of compound BBECE was studied by cyclic voltammetry analysis. The absorption and emission spectra of BBECE was experimentally determined in several solvents and simultaneously computed using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The calculated absorption and emission wavelengths are coincident with the measured data. The lowest-lying absorption spectra can be mainly attributed to intramolecular charge transfer (ICT), and the fluorescence spectra can be mainly described as originating from an excited state with intramolecular charge transfer (ICT) character. The molecular orbitals (HOMO and LUMO), the ionization potential (IP), the electron affinity (EA) and reorganization energy of compound BBECE were also investigated using density functional theory (DFT). The results show that compound BBECE exhibited excellent thermal stability and electrochemical stability as well as high fluorescence quantum yield, indicating its potential applications as an excellent optoelectronic material in optical fields.Graphical abstractHighlights► Compound contains two benzothiazole rings as electron acceptors and two N-ethylcarbazole groups as electron donors. ► Compound exhibits excellent thermal stability and electrochemical stability as well as high fluorescence quantum yields. ► Compound might be used as excellent optoelectronics materials in optical field.

Two novel pyrazoline derivatives, named 2,8-bis(1,3-diphenyl-pyrazoline-5-yl)dibenzofuran (A) and 2,8-bis(1-(4-bromophenyl)-3-phenyl-pyrazoline-5-yl)dibenzofuran (B), were synthesized and characterized by elemental analysis, NMR, MS and thermogravimetric analysis. The absorption and emission spectra of them were determined by experimental methods in different polar solvents and were computed using the density functional theory (DFT) and the time-dependent density functional theory (TDDFT) at the same time. The calculated absorption and emission wavelengths are in good agreement with the experimental data. The fluorescence quantum yields and fluorescence lifetimes of them in different polar solvents were studied by means of steady state and time resolved fluorescence. The calculated reorganization energy for hole and electron indicates that the two compounds are in favor of hole transport than electron transport. The results show the two compounds present high fluorescence quantum yields and excellent thermal stability. It makes them of great interest as novel fluorescent probes and optoelectronic materials.Graphical abstractHighlights► Pyrazoline derivatives based on the dibenzofuran contain two pyrazoline rings as electron-donors and a dibenzofuran ring as electron-acceptor. ► Pyrazoline derivatives exhibit good thermal stability and high fluorescence quantum yields. ► Pyrazoline derivatives could be used as excellent optoelectronics materials in optical field.

Three new D–π–A type compounds, each containing one benzothiazole ring as an electron acceptor and one N-ethylcarbazole group as electron donor, were synthesized and characterized by elemental analysis, NMR, MS and thermogravimetric analysis. The absorption and emission spectra of three compounds were experimentally determined in several solvents and were simultaneously computed using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The calculated reorganization energy for hole and electron indicates that three compounds are in favor of hole transport than electron transport. The calculated absorption and emission wavelengths are well coincident with the measured data. The calculated lowest-lying absorption spectra can be mainly attributed to intramolecular charge transfer (ICT). And the calculated fluorescence spectra can be mainly described as originating from an excited state with intramolecular charge transfer (ICT) character. The results show that three compounds exhibited excellent thermal stability and high fluorescence quantum yields, indicating their potential applications as excellent optoelectronic material in optical field.Graphical abstractHighlights► Compounds contain one benzothiazole ring as an electron acceptor and one N-ethylcarbazole group as electron donor. ► Compounds exhibit good thermal stability and high fluorescence quantum yields. ► Compounds might be used as fluorescent probe in biological systems. ► Compounds might be used as excellent optoelectronics materials in optical field.

The geometric structures of 10-hydroxybenzo[h]quinoline zinc [Zn(BQ)2] complex and its derivatives substituted by cyano-groups in the ground state and the lowest singlet excited state were optimized by B3LYP and ab initio CIS methods at LanL2DZ level, respectively. The absorption and emission spectra of these complexes were investigated by the time-dependent density functional theory (TD-DFT) level with PCM model on the basis of the optimized ground and excited states geometries, respectively. The calculated lowest-lying absorptions of all complexes were attributed to ILCT transitions mainly. The calculated emissions of complexes can be described as originated from an excited state with ILCT character mainly. The calculated results showed that the absorption and emission maximums could be tuned by changing the site of the substitutions. The Zn(BQ)2 and its derivatives substituted by cyano-groups were potential electroluminescent materials with blue, green and yellow light emission.

A novel intramolecular donor–acceptor compound has been synthesized and characterized. This compound was a symmetrical A–π–D–π–A type molecule containing two benzimidazole rings as two electron acceptors (A) and an N-ethylcarbazole group as electron donors (D). The absorption and emission spectra of the compound were determined by experimental methods in solution and were computed by using the density functional theory (DFT) and the time-dependent density functional theory (TDDFT) in gas phase and in chloroform solution. The calculated absorption and emission wavelengths were in good agreement with the experimental ones. The fluorescence quantum yields and fluorescence lifetimes of the compound in several solvents have been studied by means of steady state and time resolved fluorescence. The results showed the compound had high quantum yield. The cross-section of two-photon absorption (TPA) of the compound was measured by using femtosecond laser in dichloromethane solution. The result indicated the cross-section maximum of two-photon absorption was 430 GM at 600 nm. These results made the compound of great interest as a new fluorescent probe and photoluminescence material.

A novel boron-containing π-conjugated compound BCCB has been synthesized by the introduction of electron-acceptors (dimesitylboron groups) at the 3,3′-positions of a carbazole dimer (electron-donor). The compound BCCB possesses excellent electrochemical properties and high fluorescence quantum yields. In addition, BCCB is a sensitive fluorescence sensor with remarkable colour changes and the results could be confirmed through theoretical calculations of the compounds BCCB and [nBu4N]+2[BCCB·(F)2]2−. Our studies indicate that BCCB could be used as an excellent optoelectronic material in OLED devices and a ratiometric fluorescent chemosensor.

Nanoparticles of a novel boron-based carbazole derivative have been reported. They exhibit efficient green fluorescence, aggregation induced ratiometric fluorescence change and green/blue fluorescent switching to sense VOCs.

A new bipolar host material based on carbazole and dimesitylboron moieties, 3,6-bis(dimesitylboryl)-9-(4-(dimesitylboryl)phenyl) carbazole (BDDPC), has been successfully synthesised and characterised by elemental analysis, nuclear magnetic resonance spectroscopy, mass spectrometry and thermogravimetric analysis. The electrochemical and photophysical properties of BDDPC are studied by both experimental and theoretical methods. BDDPC exhibits excellent thermal stability (Td = 234 °C), electrochemical stability, high fluorescence quantum yield (0.95) and high triplet energy (2.83 eV). A red phosphorescent organic light-emitting diode (PhOLED) device comprising BDDPC as the host material and Os(bpftz)2(PPh2Me)2 as the dopant is fabricated and displays promising electrophosphorescence properties with a turn-on voltage of 3.0 V, a maximum brightness of 12337 cd m−2 and a maximum current efficiency of 11.04 cd A−1. Similarly, BDDPC is used to fabricate a green PhOLED device with Ir(ppy)2(acac) as the dopant, possessing a turn-on voltage of 2.5 V, a maximum brightness of 26473 cd m−2 and a maximum current efficiency of 38.60 cd A−1. Furthermore, a blue PhOLED device with BDDPC as the host material and FIrpic as the dopant is fabricated with a turn-on voltage of 3.0 V, a maximum brightness of 7622 cd m−2 and a maximum current efficiency of 7.39 cd A−1. It is anticipated that BDDPC has great potential in manufacturing PhOLED devices for display or lighting applications.