25-10-2011: The dramatic influence of polymer processing conditions on the performance of polymer solar cells is highlighted by a new paper in the Journal of Polymer Science: Polymer Physics. 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.
Original publication: O. G. Reid, J. A. Nekuda Malik, G. Latini, S. Dayal, N. Kopidakis, C. Silva, N. Stingelin, G. 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.
For Nature and chemists alike, making atmospheric nitrogen available for the formation of more complex nitrogen compounds is both essential and difficult. Paul Chirik and Scott Semproni at Princeton University, USA, report the first examples of the use of group 4 metallocene complexes for b ... more
Irradiation with light is an established method for initiating polymerization or crosslinking (curing) in the production of plastics. American researchers are now using light to retroactively increase the size of the pores within a polymer network. As reported in the journal Angewandte Chem ... more
Approximately one third of all fragrances on the market contain vetiver oil as a key ingredient, for which no synthetic odorant is commercially available. Instead it has to be distilled from the dried roots of vetiver grass. To find out about the structural requirements of vetiver odorants, ... more
Wiley-VCH publishes monographs, textbooks, major references works and journals in print or online. Wiley-VCH can look back on over 80 years of publishing in chemistry, materials sciences, physics and the life sciences. more
More about Imperial College of London
Contact
Imperial College of London
South Kensington Campus
SW7 2AZ London
United Kingdom
The dramatic influence of polymer processing conditions on the performance of polymer solar cells is highlighted by a new paper in the Journal of Polymer Science: Polymer Physics. The study resolves some of the discrepancies found between experimental results from previously published studi ... more
Carbon nanotubes can be functionalised on a large scale more cleanly and efficiently than before, improving their commercial viability for engineering, catalysis and bionanotechnology.
Milo Shaffer and colleagues have exploited existing surface oxide defects present in most carbon nanotube ... more
Air Force Office of Scientific Research-funded Professors Mark L. Brongersma of Stanford University and Stefan A. Maier of Imperial College London are investigating new applications for terahertz sensors.
Based on their research, these sensors could be used for improving optical sources, d ... more
The latest national survey of 100% biodiesel (B100) "blend stock" samples by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) found that 95% of the samples from 2011-12 met ASTM International fuel quality specifications. The ASTM standards serve as guidelines for ... more
Employees of the U.S. Department of Energy's (DOE)'s National Renewable Energy Laboratory (NREL) were recently recognized by industry peers for their work in grid integration, industry advancement and electrochemistry. NREL was also named an Outstanding Large Company by IEEE.
Utility Variab ... more
The dramatic influence of polymer processing conditions on the performance of polymer solar cells is highlighted by a new paper in the Journal of Polymer Science: Polymer Physics. The study resolves some of the discrepancies found between experimental results from previously published studi ... more