Industry News




02/22/2013

Silicon Nanocrystal LEDs

 
New applications for LED continue to make noise in the world of facility management and building operation.

Photo: F. Maier-Flaig, KIT/LTI

LED lighting often manages to find its way into the facility management spotlight.  Scientists of KIT and the University of Toronto/Canada have now succeeded in manufacturing silicon-based light-emitting diodes (SiLEDs). They are free of heavy metals and can emit light in various colors. The team of chemists, materials researchers, nanoscientists, and opto-electronic experts presents its development in the “Nano Letters” journal (DOI: 10.1021/nl3038689).

Silicon dominates in the microelectronics and photovoltaics industries, but has been considered unsuitable for light-emitting diodes for some time. However, this is not true for nanoscopic dimensions: Minute silicon nanocrystals can produce light. These nanocrystals consist of a few hundred to thousand atoms and have a considerable potential as highly efficient light emitters, as was demonstrated by the team of Professor Uli Lemmer and Professor Annie K. Powell from KIT as well as Professor Geoffrey A. Ozin from the University of Toronto. In a joint project, the scientists have succeeded in manufacturing highly efficient light-emitting diodes from the silicon nanocrystals.

So far, manufacture of silicon light-emitting diodes has been limited to the red visible spectral range and the near infrared. As regards the efficiency of silicon diodes emitting red light, researchers from Karlsruhe are already top in the world. “Controlled manufacture of diodes emitting multicolor light, however, is an absolutely novelty,” says Florian Maier-Flaig, scientist of the Light Technology Institute (LTI) of KIT and doctoral student of the Karlsruhe School of Optics and Photonics (KSOP).

KIT scientists specifically adjust the color of the light emitted by the diodes by separating nanoparticles depending on their size. “Moreover, our light-emitting diodes have a surprising long-term stability that has not been reached before,” Maier-Flaig says. The increased service life of the components in operation is due to the use of nanoparticles of one size only. This enhances the stability of the sensitive thin-film components. Short circuits due to oversized particles are excluded.

The development made by the researchers from Karlsruhe and Toronto is also characterized by an impressing homogeneity of the luminous areas. The KIT researchers are among the few teams in the world that know how to manufacture such devices. “With the liquid-processed silicon LEDs that may potentially be produced on large areas as well as at low costs, the nanoparticle community enters new territory, the associated potentials of which can hardly be estimated today. But presumably, textbooks about semiconductor components have to be rewritten,” says Geoffrey A. Ozin, who is presently working as a KIT distinguished research fellow at KIT’s Center for Functional Nanostructures (CFN).

The SiLEDs have the advantage that they do not contain any heavy metals. In contrast to cadmium selenide, cadmium sulfide or lead sulfide used by other groups of researchers, the silicon used by this group for the light-emitting nanoparticles is not toxic. Moreover, it is available at low costs and highly abundant on earth.

 

 


Visit our website today to learn about the design flexibility of a Morton building and the endless possibilities of partnering with our designBUILD team.


Wood construction is both cost and energy efficient. Check out Morton Buildings and our designBUILD team online today to discover all the benefits of post-frame construction.


When choosing a metal-clad building for your next construction project, consider Morton Buildings, Inc., and their designBUILD team, we’ll make your dream a reality.

We Can Help You Reduce Energy by 30%

Our mission is to help our customers manage their buildings' energy costs, improve reliability, and enhance performance while having a positive impact on the environment.
CLICK HERE to find out how.

 


Visit our website today to learn about the design flexibility of a Morton building and the endless possibilities of partnering with our designBUILD team.


Wood construction is both cost and energy efficient. Check out Morton Buildings and our designBUILD team online today to discover all the benefits of post-frame construction.


When choosing a metal-clad building for your next construction project, consider Morton Buildings, Inc., and their designBUILD team, we’ll make your dream a reality.

We Can Help You Reduce Energy by 30%

Our mission is to help our customers manage their buildings' energy costs, improve reliability, and enhance performance while having a positive impact on the environment.
CLICK HERE to find out how.


 
comments powered by Disqus
05/22/2015

Initiatives will improve lamp efficiency and lighting controls.

05/21/2015

Building policy highlighted as best in the nation.

05/20/2015

Healthcare facilities focus on recycling, safer chemicals.

05/19/2015

Building design has a measureable impact on educational outcomes.

05/18/2015

Glass design repels water and boosts photovoltaic output.

05/15/2015

New method could improve sustainability, cut price of wind power.

05/14/2015

ASHRAE guideline will calculate cooling needs and cut plug loads.

05/13/2015

Legislation will improve green performance in commercial buildings.

05/12/2015

Dropping costs, improved efficiency cited as reasons for increased use.

05/11/2015

New goal to keep state under global warming threshold.

05/08/2015

Largest floor space increases found in healthcare, retail sectors.

05/04/2015

New efficiency measures will affect over 2,000 buildings.

05/01/2015

Device produces images indefinitely.

04/30/2015

Overall energy consumption growth will be modest through 2040.

04/29/2015

Over 400 buildings take part in the EPA’s Federal Green Challenge.

04/28/2015

Fortune 200 companies use green certification to verify sustainability, energy savings.

04/27/2015

New policy will affect over 1,000 buildings.

04/24/2015

New technology could reduce risk of hospital-acquired infections.

04/23/2015

Seismic activity shown to affect nearly half of Americans.

04/22/2015

New technologies will cut use of climate-damaging refrigerants.

Sponsored Links