An anthracene-containing poly(arylene-ethynylene)alt-poly(arylene-vinylene) (PAE-PAV) of general constitutional unit (APhACBCAAnthrACBCAPhACH@CHAAnthrACH@CH) n bearing two 2-ethylhexyloxy solubilizing side chains on each phenylene (Ph) unit has been synthesized and characterized. The basic electrochemical characterization was done, showing the existence of two non-reversible oxidation and one reversible reduction peaks. The optical properties, the real and imaginary part of the dielectric function, were probed using spectroscopic ellipsometry (SE). The vibrational structure of the undoped/doped polymer was investigated using Fourier transformed infrared spectroscopy. A strong change in the polaronic absorption was observed during the doping, which after modeling revealed the existence of two separated transitions. The optical changes upon doping were additionally recorded using the SE technique. Similar to the results from FT-IR spectroscopy, two new in-the-gap absorptions were found. Moreover, the electrical conductivity as well as the mobility of positive carriers were measured. In the undoped state, the conductivity of the polymer was found to be below the detection limit (

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Four conjugated polymers (P1-P4) consisting of alternating anthracene-9,10-diyl and 1,4-phenylene building blocks connected via ethynylene as well as vinylene (P1 and P2), ethynylene-only (P3), and vinylene-only (P4) moieties, respectively, were synthesized and studied. The phenylene units in all four polymers bear 2-ethylhexyloxy side-chains to promote good solubility. The three polymers with vinylene units (P1, P2, and P4) were prepared using the Horner-Wadsworth-Emmons reaction. For the synthesis of the aryleneethynylene polymer P3, the palladium-catalyzed Sonogashira cross-coupling reaction was used. The polymers were characterized by NMR, Fourier transform infrared spectroscopy, and Raman spectroscopy. Photophysical, absorption and photoluminescence, and electrochemical properties were studied. Spectroscopic ellipsometry measurements were performed to gain more insight on the optical properties. In addition, the transport properties were investigated using admittance spectroscopy. The bulk hole mobility and its dependence on the electric field were evaluated for P1 and P2.

High performance organic solar cells were realized using an anthracene-based polymer. Charge carrier mobilities of both electrons and holes in solvent annealed polymer and fullerene derivative mixtures were studied using organic field-effect transistors. Fine tuning of donor to acceptor ratios revealed optimum conditions for balanced mobilities, which led to a high power conversion efficiency (PCE) of 4.02% in the organic solar cells. A methanol wash approach further enhanced the PCE to 4.65%. This work demonstrates the importance of carrier transport control in optimizing the performance of polymer solar cells.Although polymer solar cells have a number of advantages over silicon based solar cells in terms of their low cost, light weight and exibility etc., one of the bottlenecks to their application is their relatively low power conversion efficiencies (PCEs). Recent advances in chemical and device engineering have pushed PCEs of polymer solar cells over 10%.1 However, for market applications, the PCE has to be further improved. The development of new materials and their integration into efficient device congurations have to be explored. One of the approaches is to fabricate tandem solar cells. Indeed, until now, the highest PCE reported for polymer solar cells was obtained using a tandem structure.2 In this conguration, two or more cells are stacked in series, thus the device open circuit voltage (V oc ) will be the sum of V oc achieved from each sub-cell. The absorption prole of the sub-cells should be complimentary in order to achieve the maximum possible short circuit current density (J sc ) from each sub-cell. Recently, identical active layers comprised of low band gap polymer were proposed with quite thin lms.3 However, for a large scale process at an industrial level thicker lms are preferred due to the requirements of homogeneity and robustness for high production yield. Therefore, both low and wider band gap polymers should be incorporated into tandem solar cells in each sub-cell, in this case, wider band gap polymers that yield high V oc are most useful. One such promising polymer is the anthracene-based PPV polymer. It has an optical band gap of about 2 eV, with a high oxidation potential, resulting in a generally high V oc in polymer solar cells when combined with [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM, classical). 4Several studies have been carried out to optimize device performance. Side chain variation has been shown to have a rather strong impact on the pi-pi stacking ability of the polymer backbone, and consequently on device performance. A PCE of 3.03% was achieved for the polymer with optimum side chain distribution, named AnE-PVstat.5 Fine tuning of macromolecular parameters such as molecular weight and polydispersity resulted in a PCE of 3.26%.6 Through the control of blend morphology, by solution concentration and PCBM weight fraction, a high PCE of 4.33% was recently achieved.7 Applying different fullerene derivatives as acceptors has been proposed, and signicant variat...