Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Let the Sun Shine in

Nanorods made of fullerenes improve performance of polymer solar cells

The biggest obstacle to making use of solar energy has been the excessively high price of solar cells made of inorganic semiconductors. In contrast, solar cells based on semiconducting polymers are affordable, light, thin, and flexible—but their performance has been lacking.

A team led by Chain-Shu Hsu at the National Chaio Tung University and Yuh-Lin Wang at Academia Sinica in Taiwan has now developed a new approach that uses fullerene nanorods to significantly increase the effectiveness of polymer-based solar cells. They introduce their work in the journal Angewandte Chemie.

In the photoactive layer of a solar cell, light energy sets electrons free. This leaves behind positively charged gaps or “holes”. Electrons and holes must be separated quickly and efficiently, or they recombine and reduce the power of the solar cell. The efficiency of a solar cell thus depends on how well the resulting charge is directed away and transported to the electrodes.

In polymer solar cells, it is possible to attain more efficient charge separation through the addition of acceptors, such as fullerenes, which take up electrons. One highly promising concept is to embed the acceptor molecules in a disordered matrix made of photoactive polymer chains. The boundary surface between the two components is thus spread over the entire layer. This construct is known as a “bulk-hetero contact”. After charge separation, the electrons and holes are located in different molecular systems, which transport them selectively to opposite electrodes.

The problem is that the two materials are not evenly distributed. The travel pathways for the charges are thus disordered, allowing holes and electrons to encounter each other easily. In addition, charge-separated islands can occur. The solution would be an “ordered bulk-hetero contact”, a periodic structure of vertically directed, interpenetrating regions of both materials. Electrons and holes would then have straight pathways that do not cross. However, it has previously not been possible to produce any effective photolayer using this principle, because the components are not molecularly intermixed, making the electron pathways too long to produce effective charge separation.

The Taiwanese researchers decided to combine the two structural principles. By using a nano-casting process, they produced a layer of vertically oriented nanorods from a cross-linking polymeric fullerene material. The spaces between the rods were filled with a mixture made from a photoactive polymer and a fullerene. This layer ensures effective charge separation, and the interpenetration of the fullerene nanorods ensures ordered – and thus effective—charge transport. Solar cells made with this novel combined photolayer are stable and achieve amazingly high performance.

Author: Chain-Shu Hsu, National Chiao Tung University, Hsin-Chu (Taiwan),
Title: Enhanced Performance and Stability of a Polymer Solar Cell by Incorporation of Vertically Aligned, Cross-Linked Fullerene Nanorods

Angewandte Chemie International Edition, Permalink to the article:

Chain-Shu Hsu | Angewandte Chemie
Further information:

More articles from Life Sciences:

nachricht North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich

nachricht Researchers Discover New Anti-Cancer Protein
22.03.2018 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

Modular safety concept increases flexibility in plant conversion

22.03.2018 | Trade Fair News

New interactive map shows climate change everywhere in world

22.03.2018 | Earth Sciences

New technologies and computing power to help strengthen population data

22.03.2018 | Earth Sciences

Science & Research
Overview of more VideoLinks >>>