Dedoping of PEDOT:PSS by a simple and physical process has been performed by the addition of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU), a strong organic base, in the PEDOT:PSS aqueous dispersion. The DBU-treated PEDOT:PSS samples showed a strong absorption band at 600 nm (π−π* transition) and a small band at 900 nm (polaronic band), which indicates that some PEDOT chains were being reduced. The dedoping efficiency depended of the amount of DBU added to the aqueous PEDOT:PSS dispersion. The DBU-treated PEDOT:PSS aqueous dispersions and films showed a strong yellow emission, visible with the naked eye, when they were excited with a 488 nm laser. In addition, the same emission features were observed using another reducing agent like sodium hydroxide (NaOH), which indicates that the emission originates from neutral PEDOT chains rather than artifacts. Finally, Raman and FTIR spectroscopies were used to figure out the mechanism responsible for the PEDOT reduction. The reduction of PEDOT chains is due to the formation of hydroxide anions, which come from the interaction of DBU with water present in the PEDOT:PSS aqueous solution and interact with the oxidized thiophene molecules, resulting in a neutralization of the PEDOT backbone.
The solubilization and micellar encapsulation of fullerene derivative [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) have been investigated by the use of the amphiphilic block copolymer polystyrene-blockpoly[ethylene oxide] (PS-b-PEO). Aqueous solutions were formed, starting from a codissolution of PCBM and PS-b-PEO in a mixture of chlorobenzene and ethanol, inducing micellization by replacing the common solvent chlorobenzene with water, using evaporation at 65 °C. The control of the experimental process has permitted us to obtain only two kinds of micellar morphologies encapsulating PCBM: small spheres whose diameters increase as a function of the PCBM concentration, from approximately 60 to 120 nm, and wormlike micelles with diameters smaller than 60 nm and lengths ranging from a few hundred nanometers to several micrometers. The optical properties reflect the expected encapsulation of PCBM. Furthermore, we show that the optical properties of the confined PCBM molecules can be modified by varying the quantity of fullerenic molecules in the micellar structures, which is due to the PCBM packing, as shown by our density functional theory (DFT) calculations.
F eF wishurnyi I D pF he end I D eF uF qorthev I D F sF sil9ev P D F wF mirnov P D xF xF pleev P I ssgy À evD n vuis otosD vD wexio P eF pF soffe hysioEehnil snstituteD ussin edemy of ienesD tF etersurgD ussi grystF esF ehnolF QQ IWWV Q RSU± ±RTR
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.