Synergistically Halogenated and Methoxylated Thiophene Additive Enables High-Performance Organic Solar Cells.

Morphology control plays a key role for improving efficiency and stability of bulk heterojunctions (BHJ) organic solar cells (OSCs). Halogenation and methoxylation are two separate ways successfully adopted in additives for morphology optimization. In this work, these two strategies are combined together.

Fully Fused Indacenodithiophene-Centered Small-Molecule n-Type Semiconductors for High-Performance Organic Electronics.

Developing novel n-type organic semiconductors is an on-going research endeavour, given their pivotal roles in organic electronics and their relative scarcity compared to p-type counterparts. In this study, a new strategy was employed to synthesize n-type organic semiconductors featuring a fully fused conjugated backbone. By attaching two sets of adjacent amino and formyl groups to the indacenodithiophene-based central cores and triggering a tandem reaction sequence of a Knoevenagel condensation-intramolecular cyclization, DFA1 and DFA2 were realized.

The anti-correlation effect of alkyl chain size on the photovoltaic performance of centrally extended non-fullerene acceptors.

Contrary to previous results, a unique anti-correlation effect of the alkyl chain size on the photovoltaic performance of acceptors was observed. For a centrally-extended acceptor, replacing linear alkyl chains (-undecyl for CH-BBQ) on the thienothiophene unit with branched ones (2-butyloctyl for CH-BO) leads to a plunge in the power conversion efficiency of organic solar cells (18.12% 11.