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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 5
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SURFACE ENGINEERING
COATING TECHNOLOGY
FINDS NEW HORIZONS
Surmet Corp., Burlington, Mass.,
contributed the critically enabling sil-
icon mirror-surface technology for the
LORRI telescope, part of NASA’s New
Horizons mission. The unique and pro-
prietary silicon coating technology is
strongly adherent, amorphous, and
supremely homogeneous at an atomic
scale. The coating applied to the mirror
substrate of the telescope allows for
single point diamond turning and finish
polishing, meeting the most stringent
wavefront specifications required for
capturing ultrahigh resolution images
from outer space. The New Horizons
mission, launched in 2006, is the first
spacecraft to travel to Pluto and the
Kuiper Belt. It traveled for nine years
to reach its milestone closest approach
to Pluto (within approximately 7750
miles) on July 14.
surmet.com.
DEPOSITION TECHNIQUE
CONTROLS NANOWIRE LENGTH
It is now possible to synthesize bi-
metallic nanowires made of silver and
gold whose length can be precisely con-
trolled, thanks to new experiments by
European researchers. Because the wires
LORRI (bottom left) took the images from the New Horizons spacecraft (top left)
of Pluto (top right). Silicon mirror surface technology from Surmet enabled image
capture (bottom right).
BRIEF
Massachusetts Institute of Technology’s
spinout company
LiquiGlide
licensed its nonstick coating to Norwegian
consumer goods producer
Orkla
for use on mayonnaise products sold in Europe. Developed in 2009, the liquid-
impregnated coating acts as a slippery barrier between a surface and a viscous liquid. Applied inside a condiment
bottle, for example, the coating clings permanently to its sides, while allowing the condiment to glide off completely.
liquiglide.com.
also have roughly the same molecular
weight, their “surface plasmon resonanc-
es” can be tailored too—in the near- and
mid-infrared regions of the electromag-
netic spectrum. These nanostructures
could be used in a variety of different ap-
plications, from metamaterials to solar
energy harvesting and biosensing.
Plasmons are quantized collective
oscillations of electrons confined on the
surface of a metal that interact strongly
with light on the nanoscale. Bimetallic
nanostructures such as nanowires, es-
pecially those made of silver and gold,
are good plasmonic materials. Because
plasmonic nanowires collect and focus
light at optical to near-infrared wave-
lengths, they are crucial for developing
future nanophotonics devices.
To tailor the surface plasmon res-
onances of nanowires for specific ap-
plications, researchers must accurately
control the length of these structures
and synthesize them so that they do
not differ too much in weight and size.
Luis Liz-Marzán of the Centro de Inves-
tigación Cooperativa en Biomateriales,
San Sebastián, and the Basque Foun-
dation for Science in Bilbao, both in
Spain, and others developed a nano
wire growth technique based on selec-
tively depositing silver onto specific
crystallographic facets of prefabricated
gold cores known as pentatwinned gold
nanorods. To obtain highly elongated
nanostructures just microns in length,
researchers avoided secondary nucle-
ation or other side reactions that would
compromise the quality of the finished
product.
www.cicbiomagune.es.