This is the accepted version of the paper.This version of the publication may differ from the final published version. with an on/off ratio of 2.5 × 10 4 , which is among the best performance of the copolymers reported for the solution-processed organic field effect transistors (OFETs). The preliminary results indicate that PTZV-PT is a promising polymer material for applications in solution-processable OFETs. Permanent repository link

Strong intermolecular interactions usually result in decreases in solubility and fluorescence efficiency of organic molecules. Therefore, amorphous materials are highly pursued when designing solution‐processable, electroluminescent organic molecules. In this paper, a non‐planar binaphthyl moiety is presented as a way of reducing intermolecular interactions and four binaphthyl‐containing molecules (BNCMs): green‐emitting BBB and TBT as well as red‐emitting BTBTB and TBBBT, are designed and synthesized. The photophysical and electrochemical properties of the molecules are systematically investigated and it is found that TBT, TBBBT, and BTBTB solutions show high photoluminescence (PL) quantum efficiencies of 0.41, 0.54, and 0.48, respectively. Based on the good solubility and amorphous film‐forming ability of the synthesized BNCMs, double‐layer structured organic light‐emitting diodes (OLEDs) with BNCMs as emitting layer and poly(N‐vinylcarbazole) (PVK) or a blend of poly[N,N′‐bis(4‐butylphenyl)‐N,N′‐bis(phenyl)benzidine] and PVK as hole‐transporting layer are fabricated by a simple solution spin‐coating procedure. Amongst those, the BTBTB based OLED, for example, reaches a high maximum luminance of 8315 cd · m−2 and a maximum luminous efficiency of 1.95 cd · A−1 at a low turn‐on voltage of 2.2 V. This is one of the best performances of a spin‐coated OLED reported so far. In addition, by doping the green and red BNCMs into a blue‐emitting host material poly(9,9‐dioctylfluorene‐2,7‐diyl) high performance white light‐emitting diodes with pure white light emission and a maximum luminance of 4000 cd · m−2 are realized.

A donor‐π‐acceptor (D‐π‐A) alternative copolymer of carbazole and thieno[3,4b]‐pyrazine [P(CZ‐TPZ)] is synthesized through a Wittig–Horner reaction. In dilute THF solution, the absorption spectrum of P(CZ‐TPZ) shows two absorption peaks at 306 and 452 nm, respectively, and the PL spectrum of the polymer solution displays a PL peak maximum at 543 nm. The polymer possesses relatively high sensitivity and selectivity for Hg2+ detection. Upon addition of Hg2+ into its THF solution (containing 0.3% CH3CN), P(CZ‐TPZ) exhibits a new absorption peak at 560∼600 nm and its emission was quenched dramatically. The Hg2+ detection shows high selectivity in comparison with the other cations of Na+, K+, Mg2+, Ba2+, Al3+, Cu2+, Cd2+, Pb2+, Ni2+, Mn2+, and Co2+. The Hg2+ detection limit of the polymer solution by emission quenching is found to be 1 × 10−7 mol L−1. P(CZ‐TPZ) also shows a selective chromogenic behavior toward Hg2+ with color change of the solution from yellow to blue dark which can be detected with the naked eye, the detection limit reaches 1 × 10−6 mol L−1 with a 1 × 10−4 mol L−1 polymer solution. The absorption and PL spectral change can be resumed after adding thiourea, therefore the sensing ability of the polymer is re‐usable with the treatment of thiourea. The results indicate that P(CZ‐TPZ) is a promising chemosensor for the Hg2+ detection.

Poly(p-phenylenevinylene) (PPV) derivatives containing the 3D π−π stacking structures of the triphenylamine moieties as two side chains have been synthesized by the Wittig−Horner reaction. The presence of 2,5-bis(4-(N,N-diphenylamino)phenylenevinylene units along these π-conjugated polymer backbone lowered the band gap, and thus the resulting polymers exhibited strong and broad absorption in the visible region. Triphenylamine groups effectively extended the conjugation length through 3D π−π stacking and enhanced the hole-transporting properties of the polymers. Furthermore, the 3D π−π stacking effects of the triphenylamine moieties on the properties of the polymer light-emitting devices (PLEDs) and photovoltaic solar cells were also investigated in detail. The maximum electroluminescence (EL) brightness of the single-layer light emitting devices for P1 and P2 achieved 3003 and 1697 cd/m2, respectively. The bulk heterojunction polymer photovoltaic cells (PPVCs) based on P1 or P2 and PCBM (1:1, w/w) showed power conversion efficiencies up to 0.27% and 0.45% under the illumination of AM 1.5, 90 mW/cm2, which were 3−5 times higher than that of the device based on P3 (0.09%) without triphenylamine side chains.