Block copolymer compatibilized polymer: fullerene blend morphology and properties

Abstract

Recent studies have shown the role of block copolymer as compatibilizer in tuning the phase separated morphology of the active layer so as to improve the overall photovoltaic efficiency of organic photovoltaic (OPV) devices. Here, we substantiate this observation by investigating the role of a rod-coil block copolymer poly-(3-hexylthiophene)-b-polystyrene (P3HT-b-PS) as compatibilizer in influencing the blend morphology and device performance of several polymer:fullerene blend systems. Fullerene derivatives N-(3-methoxypropyl)-2-(carboxyethyl)-5-(4-cyanophenyl) fulleropyrrolidine (NCPF) and N-(3-methoxypropyl)-2-(carboxyethyl)-5-(5, 5-difluorobenzo-dioxole) fulleropyrrolidine (FFNCPF) were synthesized using Prato reaction, while P3HT-b-PS copolymer was synthesized using the combination of Grignard metathesis, ATRP, and click chemistry.

Tackling Performance Challenges in Organic Photovoltaics: An Overview about Compatibilizers

“…Block copolymers incorporating both P3HT and poly(styrene) portions are well-known polymeric CBs, widely reported to improve the morphology of P3HT blends in combination with PCBM [140] or other fulleropyrrolidine derivatives [141]. An "exotic" approach has been recently referred to by Mohammadi-Arbati and colleagues, who have reported the combined addition of a rod-coil block copolymer comprising P3HT and polystyrene (P3HT-b-PS), and reduced graphene oxide nanosheets grafted with regioregular poly(3-hexylthiophene) (rGO-g-P3HT) as compatibilizers in a typical P3HT:PCBM blend [142].…”

“…One very recent example concerning a P3HT:PCBM OPV device looks interesting for opening discussion over some "confusing" terminology. In the paper from Xu and coworkers [143], they describe an OPV based on the classic architecture P3HT:PCBM, where a compatible low-bandgap polymer is added, PCBTDPP, in order to act as a "bridge" between the main donor and acceptor units, Block copolymers incorporating both P3HT and poly(styrene) portions are well-known polymeric CBs, widely reported to improve the morphology of P3HT blends in combination with PCBM [140] or other fulleropyrrolidine derivatives [141]. An "exotic" approach has been recently referred to by Mohammadi-Arbati and colleagues, who have reported the combined addition of a rod-coil block copolymer comprising P3HT and polystyrene (P3HT-b-PS), and reduced graphene oxide nanosheets grafted with regioregular poly(3-hexylthiophene) (rGO-g-P3HT) as compatibilizers in a typical P3HT:PCBM blend [142].…”

Fabrication Processes to Generate Concentration Gradients in Polymer Solar Cell Active Layers

“…Accordingly, inverted devices prepared with C-PCPDTBT, which display such concentration gradient, exhibit higher performances (PCE of 3.89%) as compared to those using Si-PCPDTBT:PC 71 BM active layers (PCE of 3.17%). Note that modifying the structure is not limited to bridging atoms and synthesis of copolymers consisting of conjugated and electrically insulating blocks or functionalizing the polymer also provide means to tune the vertical concentration gradients in PSC active layers [ 60 , 61 ].…”

Morphology and mechanical properties of Acrylonitrile‐styrene‐acrylate toughened plastics with block copolymer chain structure

“…Block copolymers are promising to solve above problems because of a well-defined molecular structure [2]. Many studies have shown that the mechanical and rheological properties of various blends are remarkably improved by adopting block copolymers [3][4][5][6][7][8][9]. Similar to anionic polymerization, controlled/ living radical polymerization (CLRP) is a powerful tool to synthesize complex polymers like block copolymers and gradient copolymers, especially suitable for polar monomers [10][11][12][13].…”