Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Materials Yield Record Efficiency Polymer Solar Cells

11.11.2014

Researchers from North Carolina State University and Hong Kong University of Science and Technology have found that temperature-controlled aggregation in a family of new semi-conducting polymers is the key to creating highly efficient organic solar cells that can be mass produced more cheaply. Their findings also open the door to experimentation with different chemical mixtures that comprise the active layers of the cells.

Polymer solar cells are a delicately controlled mixture of a polymer donor and a fullerene acceptor. The cell is created by adding a solvent to the polymer and fullerene until the mixture becomes a liquid, then spreading the liquid thinly onto a surface.


Temperature-controlled aggregation in a family of new semi-conducting polymers appears to be the key to creating highly efficient organic solar cells that can be mass produced more cheaply.

As the solvent evaporates, the thin layer solidifies, with the donor material hardening into tiny, highly ordered “clumps” that are connected by other, disordered donor molecules, and the acceptor weaving around them. Currently the most efficient organic solar cells are manufactured using one of only two different fullerenes.

NC State physicist Harald Ade and postdoctoral researcher Wei Ma had previously studied the morphology of solar cells and found that the size scale of the clumps within the donor layer and the aggregation – or interaction between neighboring molecules within the layers – were the main drivers of solar cell efficiency.

In a paper published today in Nature Communications, Ade, Ma and a team of chemists from the Hong Kong University of Science and Technology led by He Yan show that size scale and aggregation within these devices are strongly temperature dependent.

They also show that record efficiencies of up to 10.8 percent – as opposed to the currently published 9.8 percent – are achievable with the substitution of numerous fullerenes. Additionally, this performance can be achieved in thick film devices.

“Once we saw how temperature affected the aggregation and morphology of these solar cells, it allowed the chemists more freedom to play with different chemical compositions in the active layer,” Ade says. “Yan’s team demonstrated 10 percent efficiency with 10different mixtures, and in thicker films.

So these solar cells could be compatible with existing methods of mass production, like slot die casting and roll-to-roll processing similar to newspaper printing, rather than the more expensive production methods currently in use that are required for thickness control.

“We hope that these findings will allow others to experiment with different polymer:fullerene blends, further increasing the efficiency of solar cells, decreasing their production costs and leading to a commercially viable alternative source of energy.”

-peake-

Note to editors: The abstract of the paper follows.

“Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells”

Authors: Yuhang Liu, Jingbo Zhao, Zhengke Li, Cheng Mu, Huawei Hu, Kui Jiang, Haoran Lin, and He Yan, Hong Kong University of Science and Technology; Harald Ade and Wei Ma, North Carolina State University
Published: Online in Nature Communications

DOI: 10.1038/ncomms6293

Abstract: Although the field of polymer solar cell has seen much progress in device performance in the past few years, several limitations are holding back its further development. For instance, current high-efficiency (>9.0%) cells are restricted to material combinations that are based on limited donor polymers and only one specific fullerene acceptor. Here we report the achievement of high-performance (efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells for multiple polymer:fullerene combinations via the formation of a near-ideal polymer:fullerene morphology that contains highly crystalline yet reasonably small polymer domains. This morphology is controlled by the temperature-dependent aggregation behavior of the donor polymers and is insensitive to the choice of fullerenes. The uncovered aggregation and design rules yield three high-efficiency (>10%) donor polymers and will allow further synthetic advances and matching of both the polymer and fullerene materials, potentially leading to significantly improved performance and increased design flexibility.

Dr. Harald Ade | EurekAlert!
Further information:
http://news.ncsu.edu/2014/11/efficient-solar-cell/

More articles from Materials Sciences:

nachricht New design improves performance of flexible wearable electronics
23.06.2017 | North Carolina State University

nachricht Plant inspiration could lead to flexible electronics
22.06.2017 | American Chemical Society

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>