Film-like conjugated microporous polymers (CMPs) are fabricated by the novel strategy of carbazole-based electropolymerization. The CMP film storing a mass of counterions acting as an anode interlayer provides a significant power-conversion efficiency of 7.56% in polymer solar cells and 20.7 cd A(-1) in polymer light-emitting diodes, demonstrating its universality and potential as an electrode interlayer in organic electronics.

This review focuses on alkyl length effects on solid-state fluorescence and mechanochromic behaviors, and the purpose is to arouse one's further attention to the alkyl-length effect in the design, synthesis and structure–property investigation of organic optoelectronic materials.

A poly(thieno[3,4‐b]‐thiophene/benzodi­thiophene) (PTB7)‐based polymer solar cell (PSC) with conventional structure can achieve a significant power conversion efficiency of 8.42%, which is realized by integrated optimization of both anode and cathode interlayers. The effects of a conjugated microporous polymer film as the anode interlayer are threefold: it enhances the contact with active layer, increases the work function and conductivity, and blocks electrons.

A new pure fluorescent blue HLCT-emitter was designed and synthesized. Highly efficient non-doped blue OLEDs with low efficiency roll-off were achieved.

2,6,9,10-tetra(p-dibutylaminostyryl)anthracene exhibited semi-disjointed frontier molecular orbital and multifunctional optical properties, including aggregation-enhanced emission, enhanced two-photon absorption activity, fluorescence response selectively to TM ions, and piezochromic luminescence. These are rarely found in cruciform configuration dyes.

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In recent years, white organic light-emitting diodes (WOLEDs) have received great attention because of their potential application in full-color flat-panel displays and solid-state lighting. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] A variety of common approaches to obtain white emission from OLEDs is the use of blends as emissive layers [1][2][3][4][5][6] and multi-layer device structures. [7][8][9][10][11] Nevertheless, both of them have some disadvantages, for instance, the intrinsic phase separation for the former and the interfacial mixing of different layers for the latter, which make WOLEDs suffer from bias-dependent electroluminescence (EL) spectra and limit their applications. Another approach to WOLEDs is the use of a single white-emitting polymer, [12][13][14][15][16] but phase stability is still a potential issue especially for a device working at a temperature close to the glass-state transition temperature (T g ) of the polymers. To achieve colorstable white EL, a cross-linked network that fixes the luminescent chromophores is an ideal structure. However, the poor solubility of cross-linked polymer networks inhibits their processability, [17][18][19][20] which is a basic factor for the fabrication of OLEDs. Here we present the first white emissive network films formed by in situ electrochemical copolymerization (ECP), and their use as emissive layers for highly efficient and color-stable WOLEDs.ECP with concurrent polymer film deposition has proven to be an especially useful method for the preparation of electroactive and conducting copolymer films. [21][22][23][24] In this method, two or several kinds of precursors are mixed in an electrolyte solution. The precursors are electrochemically oxidized and the coupling reaction between the monomers occurs at the electrode surface with deposition of the copolymer film onto the electrode as is shown in Scheme 1, thus it is an in situ method to process cross-linked polymer network films. Films obtained by this method exhibit excellent structural and phase stability because the cross-linked structures in ECP films fix the position of the molecules and avoid phase separation in ECP films. The monomers dispersed in ECP films are uniform because the oxidation of monomers is random. The above advantages of ECP films are the essence of the present studies of highly efficient and color-stable WOLEDs. By utilizing the ECP films as emitters in WOLEDs, the devices emit illumination-quality white light with high brightness, high luminous efficiency, a high color rendering index (CRI), and extremely stable Commission Internationale d'Eclairage (CIE) coordinates.To achieve a full coverage of the whole visible spectroscopic range and high efficiency in white emissive ECP films, we used three electroactive and highly blue, green, and red fluorescent compounds as ECP precursors. The blue-, green-, and red-emissive molecules TCPC, TCBzC, and TCNzC, are fluorene-based compounds with an emission-adjustive unit and peripheral carbazole groups (see Scheme 1). Wid...

Organic light-emitting diodes (OLEDs) with conjugated organic molecules as fluorescent emitters continue to attract significant interest because they have flexible molecular structures and are easy to prepare and abundant resources of organic fluorophores. [1] To date, while red, green, and even ordinary blue emitters with desirable electroluminescence (EL) efficiencies have been achieved, highly efficient organic emitters exhibiting the near-ultraviolet (NUV) EL (such as with emission peak at Low charge injection and unbalanced carrier transport are unfavorable factors for highly efficient near-ultraviolet (NUV) electroluminescence (EL) emitters. The construction of weak donor-and acceptor-containing fluorophores has been utilized as a common solution to these issues. Few fluorescent emitters simultaneously exhibiting NUV emission and high/balanced charge-transport properties have been reported. Herein, a new 1D donor-π-acceptor molecule 9-(4′-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)-[1,1′-biphenyl]-4-yl)-9H-carbazole named PCZTZ consisting of 9-phenylcarbazole as a donor and 2,3,4-triphenyl-1,2,4-triazole as an acceptor with a biphenyl π-bridge is constructed. The backbone-twisted PCZTZ exhibits not only strong solid-state NUV fluorescence but also high and balanced hole and electron mobilities (both up to 10 −4 cm 2 V −1 s −1 ), benefiting from the 3D supramolecular H-bonding network containing strong CH⋯N interactions. Remarkably, a fabricated nondoped light-emitting diode (OLED) emits 408 nm bright NUV light with a maximal external quantum efficiency of 6.57% and Commission Internationale de L'Eclairage coordinates of (0.17, 0.07). Thus, this OLED is the most efficient NUV OLED reported thus far. These results provide a valuable strategy for the design of highly efficient NUV EL emitters by modulating the linking positions of carbazole and triazole on a biphenyl bridge.