Nanocomposite film could lead to more efficient solar cells

 
Post new topic   Reply to topic    Institute of Nanotechnology Forum Index -> Nanoenergy
View previous topic :: View next topic  
Author Message
nanoorg
Site Admin


Joined: 16 Mar 2004
Posts: 1392

PostPosted: Fri Oct 05, 2007 1:58 pm    Post subject: Nanocomposite film could lead to more efficient solar cells Reply with quote

Nanocomposite film could lead to more efficient solar cells

by James Tyrrell


A nanocomposite film could lead to more efficient solar cells as well as photocatalytic reactors that use visible light to kill bacteria and viruses, claim scientists. The team from the University of Illinois at Urbana-Champaign embedded p-type palladium oxide nanoparticles in an n-type titanium oxide matrix to create a photocatalyst with useful absorption properties.

"The 'red shift' allows the photocatalyst to absorb visible light by extending the active region of the nanocomposite from UV to the visible," says team member Jian Ku Shang. "As a result, a greater portion of the solar spectrum may be used to drive electronic devices powered by this new material."

Interestingly, the "red shift" in absorption to longer wavelengths runs contrary to the quantum size effect. As semiconductor nanoparticles decrease in size, their excitation energy generally increases, which results in a "blue shift" of their absorption band to a shorter wavelength region. In Shang's work, it appears that this mechanism is disrupted by the interaction between the ultra-fine palladium oxide (PdO) particles and the titanium oxide (TiO2) matrix.

Embedding the ultra-fine semiconductor particles into a thin-film matrix proved to be a challenge. The researchers used an electron beam to evaporate TiO2 and PdO pellets, while at the same time bombarding the growing structure with nitrogen ions. The group found that so-called ion–beam-assisted deposition helped to minimize the size of the embedded PdO particles to just a few nanometers, which gave a highly dispersed matrix.

Satisfied with the production process, Shang is looking ahead. "Our next step is to design sensors and photocatalytic reactors that take advantage of the unique optoelectronic properties of our nitrogen-doped TiO2/PdO material," he explained. "We have filed US and international patent applications and are now discussing technology transfer with industrial partners."

The researchers reported their work in Appl. Phys. Lett.





Source: http://nanotechweb.org/articles/news/6/3/13/1



Story first posted: 14th March 2007.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Institute of Nanotechnology Forum Index -> Nanoenergy All times are GMT
Page 1 of 1
 

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2002 phpBB Group