The study resolves some of the discrepancies found between experimental results from previously published studies and highlights that processing and molecular weight need to be carefully controlled to ensure maximum solar cell performance.
Teams led by Natalie Stingelin from Imperial College, London and Garry Rumbles from the National Renewable Energy Lab in Boulder, Colorado collaborated on the work to study the generation of charge carriers in neat poly(3-hexylthiophene) (P3HT) solar cells and how it depends on the polymer solid-state microstructure.
They are able to control the morphology from stacked, non-entangled chains in low-molecular-weight P3HT through to mixed stacked and amorphous, entangled phases in samples with higher molecular weight. The researchers find that it is easiest to separate charges when there are both crystalline and amorphous regions.
In previous studies on P3HT, other researchers have found yields of free charges appearing after photoexcitation can vary enormously between 1% and 15%; this work reveals that different polymer microstructures could account for that variation.
Obadiah G. Reid, Jennifer A. Nekuda Malik, Gianluca Latini, Smita Dayal, Nikos Kopidakis, Carlos Silva, Natalie Stingelin, and Garry Rumbles, “The influence of solid-state microstructure on the origin and yield of long-lived photogenerated charge in neat semiconducting polymers”, J. Polym. Sci. Part B: Polym. Phys., 2011, DOI: 10.1002/polb.22379.
This article is available online at http://onlinelibrary.wiley.com/doi/10.1002/polb.22379/abstract.
Carmen Teutsch | Wiley-VCH
Machine-learning predicted a superhard and high-energy-density tungsten nitride
18.07.2018 | Science China Press
In borophene, boundaries are no barrier
17.07.2018 | Rice University
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Materials Sciences
18.07.2018 | Life Sciences
18.07.2018 | Health and Medicine