TY  - JOUR
A1  - Landfester, Katharina
A1  - Montenegro, Rivelino V. D.
A1  - Scherf, Ullrich
A1  - Günter, R.
A1  - Asawapirom, Udom
A1  - Patil, S.
A1  - Neher, Dieter
A1  - Kietzke, Thomas
T1  - Semiconducting polymer nanospheres in aqeous dispersion prepared by a miniemulsion process
Y1  - 2002
ER  - 
TY  - JOUR
A1  - Asawapirom, Udom
A1  - Bulut, F.
A1  - Farrell, Tony
A1  - Gadermaier, C.
A1  - Gamerith, S.
A1  - Güntner, Roland
A1  - Kietzke, Thomas
A1  - Patil, S.
A1  - Piok, T.
A1  - Montenegro, Rivelino V. D.
A1  - Stiller, Burkhard
A1  - Tiersch, Brigitte
A1  - Landfester, Katharina
A1  - List, E. J. W.
A1  - Neher, Dieter
A1  - Torres, C. S.
A1  - Scherf, Ullrich
T1  - Materials for polymer electronics applications semiconducting polymer thin films and nanoparticles
N2  - The paper presents two different approaches to nanostructured semiconducting polymer materials: (i) the generation of aqueous semiconducting polymer dispersions (semiconducting polymer nanospheres SPNs) and their processing into dense films and layers, and (ii) the synthesis of novel semiconducting polyfluorene-block-polyaniline (PF-b-PANI) block copolymers composed of conjugated blocks of different redox potentials which form nanosized morphologies in the solid state
Y1  - 2004
SN  - 1022-1360
ER  - 
TY  - JOUR
A1  - Kietzke, Thomas
A1  - Neher, Dieter
A1  - Kumke, Michael Uwe
A1  - Montenegro, Rivelino V. D.
A1  - Landfester, Katharina
A1  - Scherf, Ullrich
T1  - A nanoparticle approach to control the phase separation in polyfluorene photovoltaic devices
N2  - Polymer solar cell devices with nanostructured blend layers have been fabricated using single- and dual- component polymer nanospheres. Starting from an electron-donating and an electron-accepting polyfluorene derivative, PFB and F8BT, dissolved in suitable organic solvents, dispersions of solid particles with mean diameters of ca. 50 nm, containing either the pure polymer components or a mixture of PFB and F8BT in each particle, were prepared with the miniemulsion process. Photovoltaic devices based on these particles have been studied with respect to the correlation between external quantum efficiency and layer composition. It is shown that the properties of devices containing a blend of single-component PFB and F8BT particles differ significantly from those of solar cells based on blend particles, even for the same layer composition. Various factors determining the quantum efficiency in both kinds of devices are identified and discussed, taking into account the spectroscopic properties of the particles. An external quantum efficiency of ca. 4% is measured for a device made from polymer blend nanoparticles containing PFB:F8BT at a weight ratio of 1:2 in each individual nanosphere. This is among the highest values reported so far for photovoltaic cells using this material combination
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Kietzke, Thomas
A1  - Stiller, Burkhard
A1  - Landfester, Katharina
A1  - Montenegro, Rivelino V. D.
A1  - Neher, Dieter
T1  - Probing the local optical properties of layers prepared from polymer nanoparticles
N2  - It is well known that the performance of solar cells based on a blend of hole-accepting and electron-accepting conjugated polymers as the active material depend crucially on the length scale of the resulting phase separated morphology. However, a direct control of this morphology is difficult if the layer is prepared from an organic solvent. To circumvent this difficulty, recently a universal method to fabricate defined nano-structured blend layer using nanoparticles dispersed in water was demonstrated. These nanoparticles were prepared with the miniemulsion method, which allows for the preparation of semiconducting polymer nanospheres (SPNs) with diameters in the range of 30 to 300 nanometres. Since the process starts from the active material dissolved in a common solvent, it can be applied to the fabrication of nanoparticles of blends of polymers with oligomers or even with inorganic materials. We present here for the first time scanning near field optical microscopy (SNOM) investigations on these novel nanostructured polymer layers. We show that by spin-coating a mixture of two different dispersions a nanoparticle monolayer with a statistically distribution of the nanoparticles can be obtained. Mixing conjugated polymer nanoparticles with some inert particles like polystyrene beads may allow for the preparation of nano-sized light emitters
Y1  - 2005
SN  - 0379-6779
ER  -