Evaluation of the photocurrent value for poly(2,5-dicyano-p-phenylene-vinylene)-co-(p-phenylene-vinylene) (DCN-PPV/PPV)

• Published in: Journal of solid state electrochemistry Vol. 20; no. 9; pp. 2551 - 2557
• Main Authors: Santos, Fábio Santana dos, Bertuzzi, Diego L., Pedroso, Alex V., Voinarovicz, Marco A., Klider, Karine C. C. W. dos S., Péres, Laura O., Garcia, Jarem R.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.09.2016; Springer Nature B.V
• Subjects: Analytical Chemistry; Block copolymers; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Cyano groups; Electrochemistry; Energy levels; Energy Storage; Evaluation; Infrared spectroscopy; Low pressure; Molecular orbitals; Original Paper; Photoelectric effect; Photoelectric emission; Physical Chemistry; Polyphenylene vinylene; Stability analysis; Thermal analysis; Conjugated polymers; Photocurrent; Cyano group; PPV-type copolymer; Photovoltaic devices
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-016-3217-4

A method to obtain poly(2,5-dicyano- p -phenylene-vinylene)-co-( p -phenylene-vinylene) (DCN-PPV/PPV) block copolymer was developed. The structural characteristics of the copolymer and its capability to generate a photocurrent were evaluated. IR spectra indicate the complete conversion of precursor copolymer into DCN-PPV/PPV at 250 °C under low-pressure conditions. The DCN-PPV/PPV polymer optical band gap was determined based on the observed UV-Vis spectral data by using Tauc’s equation. The two linear regions in the Tauc curve (E g  = 2.63 eV and 2.02) revealed the formation of a block copolymer. Thermal analysis showed that DCN-PPV/PPV has a higher stability than PPV and starts to degrade at 317 °C in air. The electronic parameters of DCN-PPV/PPV (IP = 5.25 eV, EA = 3.30 eV, and E g  = 1.95 eV) indicate that the cyano groups reduce the LUMO energy level without affecting the HOMO energy by much. DCN-PPV/PPV photoactivity measurements show higher photocurrent values compared to those for PPV.