Welcome to DU!
The truly grassroots left-of-center political community where regular people, not algorithms, drive the discussions and set the standards.
Join the community:
Create a free account
Support DU (and get rid of ads!):
Become a Star Member
Latest Breaking News
General Discussion
The DU Lounge
All Forums
Issue Forums
Culture Forums
Alliance Forums
Region Forums
Support Forums
Help & Search
Monolithic perovskite/silicon tandem solar cell achieves record efficiency
http://www.helmholtz-berlin.de/pubbin/news_seite?nid=14342&sprache=en&typoid=5272[font face=Serif]28.10.2015
[font size=5]Monolithic perovskite/silicon tandem solar cell achieves record efficiency[/font]
[font size=4]Teams from the Helmholtz-Zentrum Berlin and École Polytechnique Fédérale de Lausanne, Switzerland, have been the first to successfully combine a silicon heterojunction solar cell with a perovskite solar cell monolithically into a tandem device. The hybrid tandem cell showed an efficiency of 18 per cent. That is the highest currently reported value for this type of device architecture. There are even prospects for the efficiency to reach as much as 30 per cent.[/font]
[font size=3]Organic-inorganic perovskite materials are one of the biggest surprises in solar cell research. In just six years, the efficiency of perovskite solar cells has increased five-fold; moreover, perovskite solar cells can be manufactured from solution and be cost-effectively printed on large areas in the future.
…
Because perovskite layers absorb light in the blue region of the spectrum very efficiently, it is useful to combine these with silicon layers that primarily convert long-wavelength red and near-infrared light. Nevertheless, the construction of these kinds of tandem cells in a monolithic stack of deposited layers has been difficult. This is because for high efficiency perovskite cells, it is usually required to coat the perovskite onto titanium dioxide layers that must be previously sintered at about 500 degrees Celsius. However, at such high temperatures, the amorphous silicon layers that cover the crystalline silicon wafer in silicon heterojunction degrades.
…
Now a team headed by Prof. Bernd Rech and Dr. Lars Korte at the HZB Institute for Silicon Photovoltaics in cooperation with HZB’s PVcomB and a group headed by Prof. Michael Graetzel at the École Polytechnique Fédérale de Lausanne (EPFL) are the first to have fabricated this kind of monolithic tandem cell. They were successful in depositing a layer of tin dioxide at low temperatures to replace the usually used titanium dioxide. A thin layer of perovskite could then be spin-coated onto this intermediate layer and covered with hole-conductor material. In addition, a crucial element in the device architecture is the transparent top contact. Typically, metal oxides are deposited by sputtering, but this would destroy the sensitive perovskite layer as well as the hole-conductor material. Therefore, the team from HZB modified the fabrication process and incorporated a transparent protective layer.
…[/font][/font]
[font size=5]Monolithic perovskite/silicon tandem solar cell achieves record efficiency[/font]
[font size=4]Teams from the Helmholtz-Zentrum Berlin and École Polytechnique Fédérale de Lausanne, Switzerland, have been the first to successfully combine a silicon heterojunction solar cell with a perovskite solar cell monolithically into a tandem device. The hybrid tandem cell showed an efficiency of 18 per cent. That is the highest currently reported value for this type of device architecture. There are even prospects for the efficiency to reach as much as 30 per cent.[/font]
[font size=3]Organic-inorganic perovskite materials are one of the biggest surprises in solar cell research. In just six years, the efficiency of perovskite solar cells has increased five-fold; moreover, perovskite solar cells can be manufactured from solution and be cost-effectively printed on large areas in the future.
…
Because perovskite layers absorb light in the blue region of the spectrum very efficiently, it is useful to combine these with silicon layers that primarily convert long-wavelength red and near-infrared light. Nevertheless, the construction of these kinds of tandem cells in a monolithic stack of deposited layers has been difficult. This is because for high efficiency perovskite cells, it is usually required to coat the perovskite onto titanium dioxide layers that must be previously sintered at about 500 degrees Celsius. However, at such high temperatures, the amorphous silicon layers that cover the crystalline silicon wafer in silicon heterojunction degrades.
…
Now a team headed by Prof. Bernd Rech and Dr. Lars Korte at the HZB Institute for Silicon Photovoltaics in cooperation with HZB’s PVcomB and a group headed by Prof. Michael Graetzel at the École Polytechnique Fédérale de Lausanne (EPFL) are the first to have fabricated this kind of monolithic tandem cell. They were successful in depositing a layer of tin dioxide at low temperatures to replace the usually used titanium dioxide. A thin layer of perovskite could then be spin-coated onto this intermediate layer and covered with hole-conductor material. In addition, a crucial element in the device architecture is the transparent top contact. Typically, metal oxides are deposited by sputtering, but this would destroy the sensitive perovskite layer as well as the hole-conductor material. Therefore, the team from HZB modified the fabrication process and incorporated a transparent protective layer.
…[/font][/font]
