1015423-45-6Relevant articles and documents
Importance of the Donor:Fullerene intermolecular arrangement for high-efficiency organic photovoltaics
Graham, Kenneth R.,Cabanetos, Clement,Jahnke, Justin P.,Idso, Matthew N.,El Labban, Abdulrahman,Ngongang Ndjawa, Guy O.,Heumueller, Thomas,Vandewal, Koen,Salleo, Alberto,Chmelka, Bradley F.,Amassian, Aram,Beaujuge, Pierre M.,McGehee, Michael D.
, p. 9608 - 9618 (2014)
The performance of organic photovoltaic (OPV) material systems are hypothesized to depend strongly on the intermolecular arrangements at the donor:fullerene interfaces. A review of some of the most efficient polymers utilized in polymer:fullerene PV devices, combined with an analysis of reported polymer donor materials wherein the same conjugated backbone was used with varying alkyl substituents, supports this hypothesis. Specifically, the literature shows that higher-performing donor-acceptor type polymers generally have acceptor moieties that are sterically accessible for interactions with the fullerene derivative, whereas the corresponding donor moieties tend to have branched alkyl substituents that sterically hinder interactions with the fullerene. To further explore the idea that the most beneficial polymer:fullerene arrangement involves the fullerene docking with the acceptor moiety, a family of benzo[1,2-b:4,5-b]dithiophene-thieno[3,4-c]pyrrole-4,6-dione polymers (PBDTTPD derivatives) was synthesized and tested in a variety of PV device types with vastly different aggregation states of the polymer. In agreement with our hypothesis, the PBDTTPD derivative with a more sterically accessible acceptor moiety and a more sterically hindered donor moiety shows the highest performance in bulk-heterojunction, bilayer, and low-polymer concentration PV devices where fullerene derivatives serve as the electron-accepting materials. Furthermore, external quantum efficiency measurements of the charge-transfer state and solid-state two-dimensional (2D) 13C{1H} heteronuclear correlation (HETCOR) NMR analyses support that a specific polymer:fullerene arrangement is present for the highest performing PBDTTPD derivative, in which the fullerene is in closer proximity to the acceptor moiety of the polymer. This work demonstrates that the polymer:fullerene arrangement and resulting intermolecular interactions may be key factors in determining the performance of OPV material systems.
Thieno[3,4-c]pyrrole-4,6-dione-3,4-difluorothiophene Polymer Acceptors for Efficient All-Polymer Bulk Heterojunction Solar Cells
Liu, Shengjian,Kan, Zhipeng,Thomas, Simil,Cruciani, Federico,Brédas, Jean-Luc,Beaujuge, Pierre M.
, p. 12996 - 13000 (2016)
Branched-alkyl-substituted poly(thieno[3,4-c]pyrrole-4,6-dione-alt-3,4-difluorothiophene) (PTPD[2F]T) can be used as a polymer acceptor in bulk heterojunction (BHJ) solar cells with a low-band-gap polymer donor (PCE10) commonly used with fullerenes. The “all-polymer” BHJ devices made with PTPD[2F]T achieve efficiencies of up to 4.4 %. While, to date, most efficient polymer acceptors are based on perylenediimide or naphthalenediimide motifs, our study of PTPD[2F]T polymers shows that linear, all-thiophene systems with adequately substituted main chains can also be conducive to efficient BHJ solar cells with polymer donors.
Method of forming rigid imide material from soluble amide ester functionalized precursors
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, (2016/06/28)
This invention relates to a method for making soluble precursors to imides, polyimides, and polymers containing imide groups, and a method of making thin films of the same by solution casting and then removing the solubilizing group to produce thermally stable and insoluble materials.
