Abstract A new semiconducting polymer based on terthiophene‐thienopyrrolodione alternating building blocks with a deep HOMO energy level (5.66 eV) is presented. The polymer is prepared by a direct heteroarylation polycondensation reaction, which is a low‐cost and green alternative to the standard Stille coupling reaction and thus avoids any use of toxic stannyl derivatives. Integrating the polymer into bulk heterojunction solar cells with [6,6]‐phenyl C71‐butyric acid methyl ester ([70]PCBM) leads to a PCE of over 6% and a high open‐circuit voltage of up to 0.94 V. To obtain these results a unique processing additive, 1‐chloronaphthalene, is used, and a relatively low concentration of [70]PCBM is used in the blend solution.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract A double conformationally restricted kinetically labile supramolecular catalytic system, the third generation, was designed and synthesized. We investigated the substrate selectivity of this system by performing competitive pairwise epoxidations of pyridyl‐ and phenyl‐appended olefins. We compared the obtained substrate selectivities to previous less preorganized generations of this system. Five different substrate pairs were investigated, and the present double conformationally restricted system showed higher normalized substrate selectivities (pyridyl versus phenyl) for two of the substrate pairs than the previous less conformationally restricted generations. As for the preorganization of the components of the system, the catalyst, and the receptor part, it was shown that for each substrate pair there was one generation that was better than the other to generate substrate‐selective catalysis.
Abstract Over the last decade, great progress has been made in the field of organic electronics. Advancements in organic syntheses as well as in device engineering enabled preparation of polymer solar cells with power conversion efficiency (PCE) exceeding 8%–9%. In search for new polymers suitable for photovoltaic applications, push–pull polymers containing thieno[3,4‐ c ]pyrrole‐4,6‐dione (TPD) motif as an electron deficient (pull) unit emerged as very promising candidates. This Trend Article summarizes research on TPD‐based polymers with a special emphasis on the structure–property relationships.
Abstract Bulk‐heterojunction solar cells are reported with an enhanced power conversion efficiency (PCE) based on a newly designed semiconducting selenophene‐thienopyrrolodione (TPD) copolymer blended with [6,6]‐phenyl C 71 butyric acid methyl‐ester. The solar cells are fabricated using simple solution processing (implying low‐cost fabrication). The relatively deep highest occupied molecular orbital (HOMO) level leads to a correspondingly high open‐circuit voltage of 0.88 V. The PCE approaches 5.8% when Clevious P VP AI4083 is used as the hole‐transport interlayer, with an optimized active layer thickness of approximately 95 nm, and a donor‐acceptor blend ratio of 1:1. A fill factor (FF) of 0.62 is achieved. The use of additives does not seem to be beneficial in this blended system, due to the achievement of proper phase separation in the as‐cast films. Also, the BHJ devices with a 3% ratio of a 1‐chloronaphthalene (CN) additive exhibit much more severe oxidative degradation from the decreased FF with a high series resistance than BHJ devices without additive. The selenophene‐TPD based BHJ solar cell is a promising candidate for high‐performance single cells with a low‐cost additive‐free fabrication and a long‐term stable operation.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Don't stand Stille: A direct heteroarylation polycondensation reaction was used for the synthesis of high-molecular-weight thienopyrroledione-based polymers (see scheme) in an impressive yield (up to 96 %) and in only a few synthetic steps. This new method is an alternative to the standard Stille coupling reaction and thus avoids formation of toxic tin by-products.