(Press-News.org) Contact information: Dr. Thomas Zoufal
presse@desy.de
49-408-998-1666
Deutsches Elektronen-Synchrotron DESY
Solar cell degradation observed directly for the first time
X-ray examination shows structural changes in 'plastics' solar cells
This news release is available in German.
With the help of DESY's X-ray light source PETRA III, researchers of Technische Universität München have, for the first time, watched organic solar cells degrade in real time. This work could open new approaches to increasing the stability of this highly promising type of solar cell. The team headed by Prof. Peter Müller-Buschbaum from the Technische Universität München (Technical University of Munich) present their observations in this week's issue of the scientific journal Advanced Materials (Nr. 46, 10 December).
Organic solar cells, especially those based on polymers are inexpensive to produce on a large scale. Thanks to their physical flexibility, they can open up new applications of photovoltaics not possible today. Moreover, they can convert light into electricity at an efficiency of more than ten per cent and could contribute significantly to a large-scale power supply based on renewable sources. However, the efficiency of organic solar cells still rapidly declines and they have a shorter service life than conventional silicon cells.
At the P03 measuring station of DESY's light source PETRA III, scientists have made the first live observations of the degradation of organic solar cells in operation. To do this, they lit a sample polymer solar cell using a solar simulator, which emits light that matches the spectrum and intensity of sunlight, and recorded the electrical characteristics of the cell over time. At intervals ranging from several minutes to as much as one hour, the researchers also looked inside the solar cell using the sharply focused X-ray beam from PETRA III. In this way they were able to watch how the interior structure of the active layer of the solar cell changed in the course of seven hours, while the efficiency of the cell decreased by around 25 per cent.
Electricity is generated in the active layer at what is known as active domains in these solar cells. Here, light is absorbed and charge carriers are released. The diameter of these active domains increased by 17 per cent during the study, from about 70 to more than 80 nanometres (millionths of a millimeter). At the same time, the mean distance between them increased by 19 per cent from 310 nanometres to around 370 nanometres, as the X-ray measurements showed.
"This suggests that during operation small sites disappear permanently in favour of larger ones," explains first author Christoph Schaffer, who is a PhD student in Müller-Buschbaum's group. "Although the domains grow, they also recede from each other, this means that their total active area shrinks. This can precisely explain the observed decline in efficiency."
"The examination explained the mechanism of degradation for the first time. It's a first step," says co-author Dr. Stephan Roth, the DESY scientist responsible for measuring station P03. "The next step involves attempting to reduce or control this growth in a targeted manner, for example, through the addition of appropriate substances. Polymer solar cells could conceivably be produced with an internal structure in which the active sites grow to their optimal size during the first hours of operation," adds Müller-Buschbaum. "The consequence of such measures could be that industrially produced cells finally cross the economically crucial efficiency threshold also for long-term operation," emphasises Roth.
Deutsches Elektronen-Synchrotron DESY is the leading German accelerator centre and one of the leading in the world. DESY is a member of the Helmholtz Association and receives its funding from the German Federal Ministry of Education and Research (BMBF) (90 percent) and the German federal states of Hamburg and Brandenburg (10 percent). At its locations in Hamburg andZeuthen near Berlin, DESY develops, builds and operates large particle accelerators, and uses them to investigate the structure of matter. DESY's combination of photon science and particle physics is unique in Europe.
INFORMATION:
Original publication
"A Direct Evidence of Morphological Degradation on a Nanometer Scale in Polymer Solar Cells"; Christoph J. Schaffer, Claudia M. Palumbiny, Martin A. Niedermeier, Christian Jendrzejewski, Gonzalo Santoro, Stephan V. Roth, Peter Müller-Buschbaum; Adv. Mat., Vol. 25, Nr. 46, S. 6760-6764, 10 December 2013; DOI: 10.1002/adma.201302854
Solar cell degradation observed directly for the first time
X-ray examination shows structural changes in 'plastics' solar cells
2013-12-09
ELSE PRESS RELEASES FROM THIS DATE:
Aging out of bounds
2013-12-09
Aging out of bounds
New demographic data show how diversely different species age -- biologists cannot explain why
This news release is available in German.
Despite aging being one the hottest topic in the media recently, scientists have ...
Polymers can be semimetals
2013-12-09
Polymers can be semimetals
Traditional plastics, or polymers, are electrical insulators. In the seventies a new class of polymers that conduct electricity like semiconductors and metals was discovered by Alan J.Heeger, Alan G. MacDiarmid and Hideki Shirakawa. This ...
Millions of hidden share trades to be revealed
2013-12-09
Millions of hidden share trades to be revealed
Millions of previously hidden US stock trades will be revealed for the first time on Monday December 9 thanks to research from a team of academics.
Previously odd lots, which are trades of less than 100 shares, ...
New insights into the immune system of the gastrointestinal tract
2013-12-09
New insights into the immune system of the gastrointestinal tract
An international team of scientists supported by the Helmholtz Zentrum München has now discovered how this complex ...
Researchers develop system for assessing how effective species are at pollinating crops
2013-12-09
Researchers develop system for assessing how effective species are at pollinating crops
From tomatoes to pumpkins, most fruit and vegetable crops rely on pollination by bees and other insect species – and the future of many of those species is uncertain. ...
Keep on exercising, researchers advise older breast cancer survivors
2013-12-09
Keep on exercising, researchers advise older breast cancer survivors
1 year of exercise can ensure steady maintenance of bone density to help prevent fractures
To build and maintain muscle strength, it is best for older breast cancer survivors to follow an ongoing exercise ...
Measuring life's tugs and nudges
2013-12-09
Measuring life's tugs and nudges
Tiny oil droplets help measure mechanical forces produced by living cells that shape tissues and organs; new method could improve diagnosis of cancer, hypertension, and many other diseases
BOSTON – As embryonic tissue ...
Penicillin equally effective as 'big gun' antibiotics for treating less severe childhood pneumonia
2013-12-09
Penicillin equally effective as 'big gun' antibiotics for treating less severe childhood pneumonia
Children hospitalized for pneumonia have similar outcomes, including length of stay and costs, regardless of whether they are treated with "big ...
New long-lived greenhouse gas discovered by University of Toronto chemistry team
2013-12-09
New long-lived greenhouse gas discovered by University of Toronto chemistry team
Chemical appears to have highest global-warming impact of any compound to date
Scientists from U of T's Department of Chemistry have discovered a novel chemical lurking in the atmosphere ...
Network theory to strengthen the banking system
2013-12-09
Network theory to strengthen the banking system
This news release is available in Spanish.
Since the beginning of the financial crises that erupted in 2008, numerous governments have injected public funds into the banking system in order to prevent the failure of some ...
LAST 30 PRESS RELEASES:
Robotic space rovers keep getting stuck. UW engineers have figured out why
New research shows how immigration status can become a death sentence during public health crisis
University of Toronto Engineering researchers develop safer alternative non-stick coating
Good vibrations: Scientists use imaging technology to visualize heat
More ecological diversity means better nutritional resources in Fiji’s agroforests
New global study shows freshwater is disappearing at alarming rates
Scientists create an artificial cell capable of navigating its environment using chemistry alone
A little salt is good for battery health
Deep-sea fish confirmed as a significant source of ocean carbonate
How to keep kids with eating disorders home after hospital stay? Therapy
Sex differences affect efficacy of opioid overdose treatment
Aligning AI with Human Values and Well-Being
Engineering the next generation of experimental physics
The scuba diving industry is funding marine ecosystem conservation and employing locals
BATMAN brings TCR therapy out of the shadows
Surrogates more likely to be diagnosed with mental illness, study finds
Columbia Engineering researchers turn dairy byproduct into tissue repair gel
Global estimates of lives and life-years saved by COVID-19 vaccination during 2020-2024
Potential trade-offs of proposed cuts to the NIH
New research simulates cancer cell behavior
COVID, over 2.5 million deaths prevented worldwide thanks to vaccines. One life saved for every 5,400 doses administered
Scuba diving generates up to $20 billion annually
Scientists advance efforts to create ‘virtual cell lab’ as testing ground for future research with live cells
How DNA packaging controls the “genome’s guardian”
Simplified models, deeper insights: Coarse-grained models unlock new potential for ionic liquid simulations
Gorillas’ personal circumstances shape their aggression towards groupmates
Which signalling pathways in the cell lead to possible therapies for Parkinson's disease
Identifying landslide threats using hydrological predictors
First graders who use more educational media spend more time reading
Exploring the meaning in life through phenomenology and philosophy
[Press-News.org] Solar cell degradation observed directly for the first timeX-ray examination shows structural changes in 'plastics' solar cells