Home > Press > Renewable energy - The tarte tatin throws a new light on photovoltaics
Layers of zinc oxide seen through an electron microscope. On the left: natural pyramid structure; on the right: structure when grown on a mould (height of images: 5 microns). © PV-LAB, EPFL/SNSF Copies or offprints must include the author’s name and may not be used for commercial purposes |
Abstract:
Do better with less. That is the challenge the researchers of the Swiss Federal Institute of Technology in Lausanne (EPFL) have set for themselves, supported by the Swiss National Science Foundation and the Federal Office of Energy. Their specialty: manufacturing solar cells that are one thousand times thinner than conventional cells. In order to boost the output of the cells, they have developed a new nanopatterning technique.
Even though silicon is one of the most abundant elements, the energy required to make silicon from sand is immense. It is for this reason, but also to reduce manufacturing costs, that Professor Christophe Ballif and his team from the Photovoltaics and Thin-Film Electronics Laboratory at the EPFL have been working for several years on thin-film silicon solar cells that are a thousand times thinner than conventional cells.
Better light absorption
There's just one catch: the thinner the cells, the less they absorb the rays of the sun and the less electricity they produce. So researchers are trying to trap light in the thin silicon layers to increase their absorption. Traditionally, thin layers of zinc oxide—a material that is very abundant, completely non-toxic, and that grows in the form of small pyramid-shaped crystals—are used for this purpose. These crystals scatter light efficiently into the underlying silicon layer. With such zinc oxide layers, even a new world record cell efficiency was achieved.
Reducing costs
But scientists are attempting to beat this record. "It is difficult to modify the natural pyramidal shape of these crystals in order to obtain even better light scattering," explains researcher Corsin Battaglia, "so we had the idea to force the crystals to grow on a different support, an inverted mould with the desired structure." The idea is as ingenious as it is simple. Once the thin layer of zinc oxide is deposited on the mould all that needs to be done is to "demould" it—as you would a tarte tatin, for example—to obtain a film with the desired structure. This procedure, described in the September edition of the journal Nature Photonics, not only increases the amount of light that is trapped, thereby increasing output, but it also has the potential to reduce the cost of the cells because of its compatibility with mass production. These are interesting arguments at a time when photovoltaics is seeking to produce electricity at a lower price than the current grid price.
Full bibliographic informationCorsin Battaglia, Jordi Escarré, Karin Söderström, Mathieu Charrière, Matthieu Despeisse, Franz-Josef Haug and Christophe Ballif (2011). Nanomoulding of transparent zinc oxide electrodes for efficient light trapping in solar cells. Nature Photonics online. doi: 10.1038/NPHOTON.2011.198, (available in PDF format from the SNSF; e-mail:
####
For more information, please click here
Contacts:
Philippe Trinchan
+41 (0)31 3082222
Dr. Corsin Battaglia
Swiss Federal Institute of Technology, Lausanne
Photovoltaics and Thin-Film Electronics Laboratory
Institute of Microtechnology
Rue A.-L. Breguet 2
CH-2000 Neuchâtel
Tel.: +41 (0)32 718 33 34
E-mail:
Internet: http://pvlab.epfl.ch
Copyright © AlphaGalileo
If you have a comment, please Contact us.Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
Related News Press |
News and information
Simulating magnetization in a Heisenberg quantum spin chain April 5th, 2024
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Govt.-Legislation/Regulation/Funding/Policy
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Chemical reactions can scramble quantum information as well as black holes April 5th, 2024
Discoveries
Chemical reactions can scramble quantum information as well as black holes April 5th, 2024
New micromaterial releases nanoparticles that selectively destroy cancer cells April 5th, 2024
Utilizing palladium for addressing contact issues of buried oxide thin film transistors April 5th, 2024
Announcements
NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024
Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024
Energy
Development of zinc oxide nanopagoda array photoelectrode: photoelectrochemical water-splitting hydrogen production January 12th, 2024
Shedding light on unique conduction mechanisms in a new type of perovskite oxide November 17th, 2023
Inverted perovskite solar cell breaks 25% efficiency record: Researchers improve cell efficiency using a combination of molecules to address different November 17th, 2023
The efficient perovskite cells with a structured anti-reflective layer – another step towards commercialization on a wider scale October 6th, 2023
Solar/Photovoltaic
Development of zinc oxide nanopagoda array photoelectrode: photoelectrochemical water-splitting hydrogen production January 12th, 2024
Shedding light on unique conduction mechanisms in a new type of perovskite oxide November 17th, 2023
Inverted perovskite solar cell breaks 25% efficiency record: Researchers improve cell efficiency using a combination of molecules to address different November 17th, 2023
Charged “molecular beasts” the basis for new compounds: Researchers at Leipzig University use “aggressive” fragments of molecular ions for chemical synthesis November 3rd, 2023
The latest news from around the world, FREE | ||
Premium Products | ||
Only the news you want to read!
Learn More |
||
Full-service, expert consulting
Learn More |
||