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Zinc porphyrin-appended dendrimers, 12PZn, 18PZn, 24PZn, and 36PZn, containing 12, 18, 24, and 36 zinc porphyrin units, respectively, were synthesized using zinc porphyrin dyad (2PZn) and triad (3PZn) as precursors. Although these dye-functionalized dendrimers all serve as chiroptical sensors for an asymmetric bipyridine (RR- and SS-Py2), the sensing capability is highly dependent on the structure of the dendritic scaffold. 2PZn, which is chiroptically silent toward Py2, turns cooperative and displays a large ICD (induced circular dichroism) response in the visible region when incorporated into 12PZn. Judging from the extents of contribution of each zinc porphyrin unit to the CD amplitudes ([Deltaepsilonmax]), the cooperativity in 24PZn (112 M-1 cm-1) is lower than that in 12PZn (196 M-1 cm-1) and much lower in dendron 4PZn (59 M-1 cm-1). In contrast, 3PZn, which is ICD-active toward Py2, hardly shows such an enhanced cooperativity when incorporated into 18PZn and 36PZn and dendron 6PZn, as well. Absorption spectroscopy suggests some unique conformational characteristics of the zinc porphyrin units in highly cooperative 12PZn.

A small amount of the 3-(hexyldimethylammonio)propane-1-sulfonate zwitterionic side chain was integrated into a diketopyrrolopyrrole ambipolar polymer to modulate its field-effect carrier-transport characteristics. It was found that such a modification can strengthen the interchain interaction, promote crystallization, and thus improve the hole and electron mobilities by 3.9- and 8.2-fold, respectively. [ABSTRACT FROM AUTHOR]

Organic conjugated porous polymers, triazine-Ph-CPP and triazine-Th-CPP, are synthesized and characterized. Without further addition of co-catalysts, triazine-Ph-CPP exhibits a HER of 16 287 μmol g−1 h−1 and an apparent quantum yield of 61.5% at 365 nm, which demonstrates that the dibenzo[b,d]thiophene sulfone and 1,3,5-triazine based polymer is a unique prototype of a highly efficient hydrogen evolution photocatalyst. [ABSTRACT FROM AUTHOR]

In this work, dithieno[3,2-a:3′,2′-j][5,6,11,12]chrysene diimides (DTCDI), an electron-deficient π-building block, were firstly incorporated into polymer main chains by using the 3,9-positions of chrysene and the α,α′-positions of thiophene units of DTCDI to connect with the 2,2′-bithiophene unit, affording copolymers P1 and P2, respectively. Due to their different connection ways the two polymers feature different optoelectronic properties. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a new strategy for the preparation of donor–acceptor conjugated copolymers, in which both donor and acceptor units derive from one mother structure. Benzo[1,2-b:4,5-b′]dithiophene-4,8-dione (BQDT) is an electron-deficient unit. From BQDT, benzo[1,2-b:4,5-b′]dithiophene (BDT) and benzo[1,2-b:4,5-b′]dithiophene-4,8-dione dioxime (BXDT) can be easily derived and serve as electron-donating and another electron-accepting unit, respectively. Based on these three units, poly(BDT-alt-BQDT) (PBQ-C24, with 2-decyltetradecyl side chains) and poly(BDT-alt-BXDT) (PBX-C8, with 2-ethylhexyl side chains) have been designed and synthesized. Their thermal, optical and electrochemical properties have been investigated. PBQ-C24 has a broad absorption spectrum in the range of 300–700 nm, while PBX-C8 can only harvest the light from 300 to 600 nm. However, the bulk heterojunction cell based on the blend of PBX-C8 and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) displays a better performance with a power conversion efficiency of 0.51%. [Copyright &y& Elsevier]