Very‐Low‐Bandgap Metallopolyynes of Platinum with a Cyclopentadithiophenone Ring for Organic Solar Cells Absorbing Down to the Near‐Infrared Spectral Region

Abstract

Two solution-processable metallopolyynes of platinum functionalized with the electron-deficient 4H-cyclopenta[2,1-b:3,4-b']dithiophen-4-one spacer and their model molecular complexes were synthesized and developed for the applications of polymer solar cells. These metallated polymers possess extremely low bandgaps of 1.44-1.53 eV which extend toward the near-infrared (NIR) range of the solar spectrum, and represent the lowest optical bandgap yet reported for platinum(II) metallopolyynes to date. The structural flexibility, processibility, and good photovoltaic performance make cyclopentadithiophenone-containing polymers prominent candidates for NIR photovoltaic applications.

Gold(III) Corroles for High Performance Organic Solar Cells

“…The long lifetimes of triplet excitons can significantly reduce exciton recombination and this is desirable for improving PCE values of OSCs. In addition, due to the strong mixing between triplet metal‐to‐ligand charge‐transfer (MLCT) and singlet ligand‐centered π→π* excited states, these organometallic complexes usually display broad absorptions in the entire visible spectral region extending up to 800 nm . The broad absorption is particularly beneficial to the improvement of OSC performance.…”

Heavy metal complex containing organic/polymer materials for bulk-heterojunction photovoltaic devices

“…Trough the weak electron-donor and strong electron-acceptor strategy, both polymers exhibited narrow bandgaps of 1.54 and 1.65 eV, respectively, with absorption spectra extended down to 800-850 nm and up to 1% of PCE for bulk heterojunction solar cells. Besides, Pt(II) containing metallopolyynes 26 and 27 based the electron-deficient 4H-cyclopenta[2,1-b:3,4-b′]dithiophen-4-one were also reported [66], with extremely low bandgaps of 1.44-1.53 eV, representing the lowest optical bandgap yet reported for platinum(II) metallopolyynes to date. Similar to previous study, no triplet excited state occurs in photoinduced charge separation of the platinumacetylide polymers/PCBM blends based BHJ solar cells.…”

New Trends in the Optical and Electronic Applications of Polymers Containing Transition‐Metal Complexes

“…P30 and P31 , functionalized with the electron‐deficient 4 H ‐cyclopenta[2,1‐b:3,4‐b’]dithiophen‐4‐one spacer, have been developed for application in polymer photovoltaic devices 43. They possess a lower bandgap than the metallopolyynes with 9,9‐dicyanomethylenefluorene and dithienyl‐thieno[3,4‐b]pyrazine spacers.…”