Scientists of the University of Luxembourg and of the Japanese electronics company TDK report progress in photovoltaic research: they have improved a component that will enable solar cells to use more energy of the sun and thus create a higher current.
The improvement concerns a conductive oxide film which now has more transparency in the infrared region. Similar attempts had been made before, but this is the first time that these films were prepared by a one-step process and, at the same time, stable in air.
“The films made at the University of Luxembourg have been exposed to air for one and half years and are still as conductive as when they were fresh prepared”, says Prof. Susanne Siebentritt, head of the laboratory for photovoltaics at the University of Luxembourg.
“It is a fantastic result, not only for solar cells, but also for a range of other technologies”, she adds. Collaborators of this study were Dr. Matěj Hála, research associate in the laboratory for photovoltaics and Shohei Fujii and Yukari Inoue, visiting scientists from TDK.
Transparent conductive oxides are used in any device combining electronics and light, like LEDs, solar cells, photodetectors or even touch screens. They have the particularity to combine the properties of metals, which are the best electrical conductors known, with those of oxides, which usually are transparent but not conductive, as for example glass. In solar cells the film has to be conductive because it constitutes the upper electrode. At the same time it has to be transparent in order for sunlight to reach the layer underneath, where the current is formed.
The oxides forming this film can be made conductive by deliberately adding impurities. Zinc oxide with aluminium added is a widely used example. In this case, the aluminium adds free electrons to the zinc oxide which are responsible for the conductivity. However, these free electrons also absorb infrared light. That means that less sun energy can pass through.
The team of the University of Luxembourg and TDK have modified the process used to make the film in order to make pure zinc oxide more conductive. “Our multidisciplinary team, benefitting from the exchange of knowledge across countries, had the idea to add an additional component - another gas plasma - in the so called sputter process. This makes the material conductive even without aluminium.” explains Prof. Siebentritt.
This method enables to have less but faster moving free electrons. “With this result, the conductivity is similar to the one with aluminium, but it enables a much better transparency in the infrared region as less free electrons cause also less absorption. That makes solar cells more efficient”, adds Dr. Matěj Hála. The findings are now published in the respected journal "Progress in Photovoltaics".
http://www.uni.lu - University of Luxembourg
Britta Schlüter | idw - Informationsdienst Wissenschaft
Move over, Superman! NIST method sees through concrete to detect early-stage corrosion
27.04.2017 | National Institute of Standards and Technology (NIST)
Control of molecular motion by metal-plated 3-D printed plastic pieces
27.04.2017 | Ecole Polytechnique Fédérale de Lausanne
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences