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

OKIsItJustMe

(19,938 posts)
Fri Jun 19, 2015, 04:31 PM Jun 2015

First solar cell made of highly ordered molecular frameworks

http://www.eurekalert.org/pub_releases/2015-06/kift-fsc061915.php
[font face=Serif]Public Release: 19-Jun-2015
[font size=5]First solar cell made of highly ordered molecular frameworks[/font]
[font size=4]New material based on metal-organic frameworks is suited for photovoltaics; publication in the journal Angewandte Chemie International Edition[/font]

Karlsruher Institut für Technologie (KIT)

[font size=3]"We have opened the door to a new room," says Professor Christof Wöll, Director of KIT Institute of Functional Interfaces (IFG). "This new application of metal-organic framework compounds is the beginning only. The end of this development line is far from being reached," the physicist emphasizes.

Metal-organic frameworks, briefly called MOFs, consist of two basic elements, metal node points and organic molecules, which are assembled to form microporous, crystalline materials. For about a decade, MOFs have been attracting considerable interest of researchers, because their functionality can be adjusted by varying the components. "A number of properties of the material can be changed," Wöll explains. So far, more than 20,000 different MOF types have been developed and used mostly for the storage or separation of gases.

The team of scientists under the direction of KIT has now produced MOFs based on porphyrines. These porphyrine-based MOFs have highly interesting photophysical properties: Apart from a high efficiency in producing charge carriers, a high mobility of the latter is observed. Computations made by the group of Professor Thomas Heine from Jacobs University Bremen, which is also involved in the project, suggest that the excellent properties of the solar cell result from an additional mechanism - the formation of indirect band gaps - that plays an important role in photovoltaics. Nature uses porphyrines as universal molecules e.g. in hemoglobin and chlorophyll, where these organic dyes convert light into chemical energy. A metal-organic solar cell produced on the basis of this novel porphyrine-MOF is now presented by the researchers in the journal Angewandte Chemie (Applied Chemistry). The contribution is entitled "Photoinduzierte Erzeugung von Ladungsträgern in epitaktischen MOF-Dünnschichten: hohe Leistung aufgrund einer indirekten elektronischen Bandlücke?" (photo-induced generation of charge carriers in epitactic MOF-thin layers: high efficiency resulting from an indirect electronic band gap?).

"The clou is that we just need a single organic molecule in the solar cell," Wöll says. The researchers expect that the photovoltaic capacity of the material may be increased considerably in the future by filling the pores in the crystalline lattice structure with molecules that can release and take up electric charges.

…[/font][/font]
Latest Discussions»Issue Forums»Environment & Energy»First solar cell made of ...