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A record breaking PCE of 12.1% is achieved by incorporating 25 wt% of DR3TSBDT into a PTB7-Th:PC71BM host matrix.

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To systematically address the intriguing question of how siloxane termini of the side chains relative to alkylterminal groups affect the various inherent properties of conjugated polymersincluding optical, electrical, and morphological characteristicswe have synthesized model polymers (PDPPTT-R TG and PDPPTT-Si TG , together with an accompanying reference PDPPTT-ref) containing an identical backbone yet possessing different terminal groups. In order to fairly compare the end functionalities by eliminating molecular weight (M n ) and polydispersity index (PDI) variations that may act as complicating factors, the polymers used in this study have been controlled to have similar M n and PDI by carefully optimizing the catalyst system and reaction conditions. Although the molecular packing and orientation behaviors of PDPPTT-R TG and PDPPTT-Si TG are very different from each other, both polymers exhibit very high mobility exceeding 4.5 cm 2 V −1 s −1 . More meaningfully, organic field-effect transistors (OFETs) based on PDPPTT-Si TG are highly stable over extended periods in humid environments. Our findings provide new insights into the molecular design strategy aimed at the simultaneous enhancement of charge-carrier mobility and ambient stability, which is of great importance for practical OFET applications.

Compared with conventional organic solar cells (OSCs) based on single donor–acceptor pairs, terpolymer‐ and ternary‐based OSCs featuring multiple donor–acceptor pairs are promising strategies for enhancing the performance while maintaining an easy and simple synthetic process. Using multiple donor–acceptor pairs in the active layer, the key photovoltaic parameters (i.e., short‐circuit current density, open‐circuit voltage, and fill factor) governing the OSC characteristics can be simultaneously or individually improved by positive changes in light‐harvesting ability, molecular energy levels, and blend morphology. Here, these three major contributions are discussed with the aim of offering in‐depth insights in combined terpolymers and ternary systems. Recent exemplary cases of OSCs with multiple donor–acceptor pairs are summarized and more advanced research and perspectives for further developments in this field are highlighted.