May 23, 2018
Low-bandgap semiconducting polymers based on sulfur-containing phenacene-type molecules for transistor and solar cell applications
Polymer Journal
- ,
- Volume
- 50
- Number
- 8
- First page
- 1
- Last page
- 11
- Language
- English
- Publishing type
- Research paper (scientific journal)
- DOI
- 10.1038/s41428-018-0072-4
- Publisher
- Nature Publishing Group
The incorporation of a highly extended π-electron system into a polymer backbone is an effective strategy to develop high-performance donor–acceptor (D–A) polymers suitable for organic electronics because this strategy can facilitate a dense π-π stacking structure, leading to efficient carrier transport. With this in mind, we developed phenanthro[1,2-b:8,7-b′]dithiophene (PDT) because this new phenacene-type molecule has a highly crystalline nature, deep HOMO level, and high hole mobility, which are characteristics known to be suitable for a donor unit in high-performance D–A polymers. In this focus review, we report recent progress in PDT-containing D-A polymers combined with various strong acceptor units. Incorporation of PDT into a polymer backbone results in deep HOMO energy levels of −5.4~−5.5 eV, strong aggregation, and a dense packing structure with a short π-stacking distance of 3.5~3.6 Å. PDT-based polymers with appropriate alkyl side chains exhibit high hole mobilities of up to 0.18 cm2 V−1 s−1 in organic field-effect transistor (OFET) devices due to their tendency to form highly ordered edge-on structures. Furthermore, we can adjust their level of molecular orientation from edge-on to face-on by increasing their molecular weight, leading to a high power conversion efficiency of over 6% in polymer solar cell (PSC) applications. These results demonstrate that PDT is a good candidate as a high-performance building block in D-A polymers.
- Link information
- ID information
-
- DOI : 10.1038/s41428-018-0072-4
- ISSN : 1349-0540
- ISSN : 0032-3896
- SCOPUS ID : 85047250696