The synthesis and characterization of two low band gap copolymers (P1 and P2) incorporating benzo[1,2-b:4,5-b']dithiophene unit substituted with octylsulfanylthienyl groups (OSBT) are here reported. These materials, designed to be employed in polymer solar cells (PSCs), were obtained from alternating OSBT and bithiophene (P1) or thienothiophene (P2) units. Their structural electrochemical and photophysical properties were investigated. They are thermally stable and soluble in organic solvents from which they easily form films. They also form π-stacks in solution, in film and display a moderate solvatochromism. These polymers were tested with [70]PCBM in bulk-heterojunction (BHJ) PSCs where they act as donor materials and [70]PCBM is the electron acceptor. The best device, obtained using a 1:3 weight ratio for the P1:[70]PCBM blend, shows a PCE around 1.5%. A broad response from 350 to 700 nm is also observed in the external quantum efficiency (EQE) curves, wider for P1 with respect to P2.
Polymers for application in organic solar cells: Bithiophene can work better than thienothiophene when coupled to benzodithiophene / Parenti, F.; Ricciardi, R.; Diana, R.; Morvillo, P.; Fontanesi, C.; Tassinari, F.; Schenetti, L.; Minarini, C.; Mucci, A.. - In: JOURNAL OF POLYMER SCIENCE. PART A, POLYMER CHEMISTRY. - ISSN 0887-624X. - 54:11(2016), pp. 1603-1614. [10.1002/pola.28014]
Polymers for application in organic solar cells: Bithiophene can work better than thienothiophene when coupled to benzodithiophene
Diana R.;
2016
Abstract
The synthesis and characterization of two low band gap copolymers (P1 and P2) incorporating benzo[1,2-b:4,5-b']dithiophene unit substituted with octylsulfanylthienyl groups (OSBT) are here reported. These materials, designed to be employed in polymer solar cells (PSCs), were obtained from alternating OSBT and bithiophene (P1) or thienothiophene (P2) units. Their structural electrochemical and photophysical properties were investigated. They are thermally stable and soluble in organic solvents from which they easily form films. They also form π-stacks in solution, in film and display a moderate solvatochromism. These polymers were tested with [70]PCBM in bulk-heterojunction (BHJ) PSCs where they act as donor materials and [70]PCBM is the electron acceptor. The best device, obtained using a 1:3 weight ratio for the P1:[70]PCBM blend, shows a PCE around 1.5%. A broad response from 350 to 700 nm is also observed in the external quantum efficiency (EQE) curves, wider for P1 with respect to P2.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
