Otro
Structure control of poly(p-phenylene vinylene) in layer-by-layer films by deposition on a charged poly(o-methoxyaniline) cushion
Registro en:
Journal of Applied Physics, v. 113, n. 14, 2013.
0021-8979
10.1063/1.4798937
WOS:000318250600082
2-s2.0-84876370822.pdf
2-s2.0-84876370822
Autor
Marletta, Alexandre
Curcino Da Silva, Silésia de Fátima
Piovesan, Erick
Campos, K. R.
Santos Silva, Hugo
De Souza, N. C.
Letícia Vega, Maria
Raposo, Maria
Constantino, Carlos J. L
Silva, Raigna A.
Oliveira Jr., Osvaldo N.
Resumen
In this paper, we demonstrate that the intrinsic electric field created by a poly(o-methoxyaniline) (POMA) cushion layer hinders the changes in molecular conformation of poly(p-phenylenevinylene) (PPV) in layer-by-layer with dodecylbenzene sulfonic acid (DBS). This was modeled with density functional theory (DFT) calculations where an energy barrier hampered molecular movements of PPV segments when they were subjected to an electric field comparable to that caused by a charged POMA layer. With restricted changes in molecular conformation, the PPV film exhibited Franck-Condon transitions and the photoexcitation spectra resembled the absorption spectra, in contrast to PPV/DBS films deposited directly on glass, with no POMA cushion. Other effects from the POMA cushion were the reduced number of structural defects, confirmed with Raman spectroscopy, and an enhanced PPV emission at high temperatures (300 K) in comparison with the films on bare glass. The positive effects from the POMA cushion may be exploited for enhanced opto-electronic devices, especially as the intrinsic electric field may assist in separating photoexcited electron-hole pairs in photovoltaic devices. © 2013 American Institute of Physics.