EVENTS, ADVANCES, AND NEWS
■ BY JEFF ECKERT
COATING MAY IMPROVE
SOLAR CELLS, LEDS
PHOTO COURTESY OF E. FRED SCHUBERT AND JONG K YU KIM,
RENSSELAER POLYTECHNIC INSTITUTE.
reflect no light at all. If used in next-generation solar cells, the coating
would allow more light and more
wavelengths to pass through the cell
surface, thus improving its efficiency.
The team also expects that the
films can be used to eliminate reflections that reduce light emissions from
LEDs, so upcoming research will focus
on solid-state lighting applications.
■ Top: Silica nanorod layers seen with
a scanning electron microscope.
Bottom: Antireflective material (left)
looks dark in contrast to other coatings.
Ateam from Rensselaer Polytechnic
Institute ( www.rpi.edu) recently
reported development of an antireflective coating that is said to be at least
ten times as effective as substances
currently used on sunglasses and computer monitors. Composed of silica
nanorods, it could be used to channel
light into solar cells or improve the
photonic emissions of LEDs.
The coating is produced by a
process that is based on a common
method for depositing silica layers onto
computer chips, but it involves growing
tiers of nanoscale rods that lie at the
same angle, the precise angle being
determined by temperature. By laying
down multiple layers at different angles,
the researchers have generated thin
films that can be used to control light.
It is believed that by creating
layers in the proper configuration, it is
possible to create a film that will
8 May 2007
Some researchers at Purdue
University ( www.purdue.edu)
recently developed a new instrument
that they have likened to the infamous
“tricorder” from Star Trek. My recollection is that the fictitious device was
useful for everything from analyzing
the chemical makeup of alien brains to
opening cans of intergalactic Vienna
sausages, so the analogy may be a bit
overstated. However, it is an interesting
chemical analysis tool that they say has
promise for detecting “everything from
cancer in the liver to explosive residues
■ Analysis of lipids in rat brain tissue.
The first (a) is an optical image, and the
rest are ion images produced using the
on luggage and biomarkers in urine” to
provide an early warning of diseases.
The device is a compact mass
spectrometer that is enhanced by a
technique called desorption electro-spray ionization (DESI), developed at
Purdue. Whereas conventional mass
spectrometers analyze samples that
are loaded into a vacuum chamber,
DESI allows an analysis to be
performed in air or directly on the
sample’s surface. The new device is
also much smaller than standard analyzers, weighing less than 20 lbs, and
does its work in a relatively short time.
For example, the team has used
the device to analyze clothes, foods,
and tablets, and it can identify
cocaine on paper money in less than
one second. It is likely that the device
will be commercially available soon,
as two companies have already been
established on the basis of DESI and
the portable mass spectrometer.
These are Prosolia, Inc. ( www.proso
lia.com), and Griffin Analytical
Technologies LLC ( www.griffinanaly
IMAGE COURTESY OF
ANGE WANDTE CHEMIE.
For 15 years or so, you have
probably been working with
the familiar JPEG format for
digital imaging, especially with
devices that use a memory
card for storage. However, if
Microsoft has its way, JPEGs may
follow PICT files into obscurity,
being supplanted by their HD
Photo format (formerly known as
Windows Media Photo).
The product was formally
introduced in March, and it is