Synthesis, characterization and photovoltaic properties of a new thiophene-based double-cable polymer with pendent fullerene group

• Published in: Polymer (Guilford) Vol. 53; no. 11; pp. 2134 - 2145
• Main Authors: Lanzi, Massimiliano, Paganin, Luisa, Errani, Francesco
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 09.05.2012; Elsevier
• Subjects: Applied sciences; Bulk heterojunction solar cells; Energy; Exact sciences and technology; fluorescence; fluorescence emission spectroscopy; Fullerene; mixing; Natural energy; Organic polymers; Photovoltaic conversion; Physicochemistry of polymers; polymerization; polymers; Polymers with particular properties; Polythiophene; Preparation, kinetics, thermodynamics, mechanism and catalysts; Solar cells. Photoelectrochemical cells; Solar energy; solubility; solvents; thermal stability; Fullerene; Polythiophene; Bulk heterojunction solar cells; Short circuit currents; Fullerene compounds; Fluorescence; Experimental study; Fill factor; Thermal stability; Open circuit voltage; Thin film; Side chain; Conjugated copolymer; Optical properties; Preparation; Supramolecular structure; Microroughness; Aromatic copolymer; Soluble compound; Oxidative polymerization; Thiophene derivative copolymer; Optical absorption
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2012.03.040

In this paper we report the synthesis of a new thiophenic 3-substituted monomer with a plastifying side chain bearing a C60-fullerene moiety at the end. The monomer has been copolymerized with 3-hexylthiophene through the simplest chemical method, namely oxidative polymerization with iron trichloride. The final copolymer, with a high fullerene content (1:1 wt/wt), was fully soluble in common organic solvents and its solubility allowed for its complete physic-chemical characterization. The copolymer thermal behavior was investigated by TGA analysis showing that the incorporation of fullerene has beneficial effects on thermal stability. The fluorescence spectroscopy showed a strong quenching of fluorescence of the copolymer main chains in film, while the AFM analysis confirmed the homogeneous morphology of its films with only very small and uniformly distributed aggregates. The photovoltaic performances of the copolymer and of a film obtained by blending the prepared monomer with poly(3-hexylthiophene) were significantly higher than those obtained using conventional materials and architectures. [Display omitted]