Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Coating copies microscopic biological surfaces

Carlo G. Pantano, distinguished professor of materials science and engineering, and director, Penn State's Materials Research Institute holds conventional doubly refracting glass which requires 15 or more alternating layers of two materials with precisely controlled thicknesses. The CEFR technique yields doubly refracting characteristics through deposition of only one coating, nanostructured by the biotemplate. He stands before equipment used for this technique.

Credit: Greg Grieco, Penn State
Carlo G. Pantano, distinguished professor of materials science and engineering, and director, Penn State's Materials Research Institute holds conventional doubly refracting glass which requires 15 or more alternating layers of two materials with precisely controlled thicknesses. The CEFR technique yields doubly refracting characteristics through deposition of only one coating, nanostructured by the biotemplate. He stands before equipment used for this technique.

Credit: Greg Grieco, Penn State

Abstract:
Someday, your car might have the metallic finish of some insects or the deep black of a butterfly's wing, and the reflectors might be patterned on the nanostructure of a fly's eyes, according to Penn State researchers who have developed a method to rapidly and inexpensively copy biological surface structures.

Coating copies microscopic biological surfaces

PA | Posted on September 17th, 2008

"Only a small fraction of mutations in evolutionary processes are successful," says Akhlesh Lakhtakia, the Charles Godfrey Binder (Endowed) Professor of Engineering Science and Mechanics. "But, evolution has gone on for at least a billion years. A huge range of biological surface architectures have been created and are available."

Lakhtakia and his colleagues, Carlo G. Pantano, distinguished professor of materials science and engineering, and director of Penn State's Materials Research Institute, and Raúl J. Martín-Palma, visiting professor, Penn State, and professor department of applied physics, Universidad Autónomia de Madrid, used the conformal evaporated film by rotation (CEFR) technique, to produce coatings that capture the micro and nano structure of biological surfaces in a thin coating of glass. The results appear in recent issues of Applied Physics Letters and Nanotechnology.

In the CEFR technique, the researchers thermally evaporate the material that forms the coating in a vacuum chamber. The object receiving the coating is fixed to a holder and rotated about once every two seconds. The researchers have coated butterfly wings and a fly, creating replicas of these templates with identical surface characteristics. The researchers are using chalcogenide glasses composed of varying combinations of germanium, antimony and selenium.

"With the right temperature, which is room temperature, and the right pressure and rotation speed, the coating process takes about 10 minutes and deposits a 500- nanometer layer," says Lakhtakia.

Some biostructures, such as moth's eyes, which are duplicated to produce moth's-eye lenses, can be mechanically created by engineers, but it is painstaking and expensive work. These lenses, that capture nearly all available light, have applications in optoelectronic and photovoltaic applications. Other biostructures do not lend themselves to synthetic reproduction.

"In that case, perhaps we need to replicate the actual structure," says Lakhtakia. "One insect has an iridescent shell that does not change colors as many shiny ones do. No one has made this type of material artificially because we do not know the mechanism by which it retains its color, but making a template from the actual insect would replicate the fine structure of the surface."

Many things in the natural world are colored not by pigment, but by surface structure. The way light interacts with the surface creates the color, rather than any tint or chemical. Reproducing the surface reproduces the color. Surface properties include not just visible light characteristics, but also infra red, thermal, stickiness and other characteristics.

Martín-Palma, Pantano and Lakhtakia's work creates either a replica template or a mold depending on what they coat. The replica of a template can be used to create a mold in a harder, less damageable material to make many copies. Molds can be combined and multiplied to create the desired surfaces.

The researchers initially looked at surfaces with optical properties because they are easy to see and identify. The structural black of some butterflies invites investigation of thermal properties as well. Creating surfaces that have micro or nanoscale patterns on solar cells, heat exchangers, reflectors and lenses can produce devices that work more efficiently.

"The whole world of biomimetics and bioinspiration is just beginning to emerge," says Martín-Palma. "Butterfly wings come in a large variety of surface structures. Eventually we may be able to take these biological structures and modify them to create other properties that do not already exist on biological surfaces."

While the researchers are still experimenting with butterfly wings, they would like to use CEFR on lotus leaves because they are super hydrophobic. Surfaces that repel water could be very useful. They also plan to look at other plant materials as potential surfaces for solar cells. Lakhtakia and Martín-Palma are organizing a small conference next year on biomimetics and bionispiration.

Pantano suggested the use of chalcogenide glass for its infrared properties, but the researchers have also tried other glasses and materials like polymers to reproduce other surfaces and their properties.

This work was supported by the Ministerio de Educacion y Ciencia (Spain) and the Penn State National Science Foundation National Nanotechnology Infrastructure Network. The researchers have filed a provisional patent application on this work.

####

For more information, please click here

Contacts:
A'ndrea Elyse Messer

814-865-9481

Copyright © Penn State

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Researchers develop artificial building blocks of life March 8th, 2024

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

Possible Futures

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Discoveries

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Materials/Metamaterials/Magnetoresistance

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Focused ion beam technology: A single tool for a wide range of applications January 12th, 2024

Catalytic combo converts CO2 to solid carbon nanofibers: Tandem electrocatalytic-thermocatalytic conversion could help offset emissions of potent greenhouse gas by locking carbon away in a useful material January 12th, 2024

Announcements

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Automotive/Transportation

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

New designs for solid-state electrolytes may soon revolutionize the battery industry: Scientists achieve monumental improvements in lithium-metal-chloride solid-state electrolytes November 3rd, 2023

Previously unknown pathway to batteries with high energy, low cost and long life: Newly discovered reaction mechanism overcomes rapid performance decline in lithium-sulfur batteries September 8th, 2023

Tests find no free-standing nanotubes released from tire tread wear September 8th, 2023

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project