Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Nanomaterials: Formation in a flash - A new lithography technique enables the production of nanoscale patterns of titania for high-tech applications

The nanoscale titania pattern before and after heat-treatment.  2012 American Chemical Society
The nanoscale titania pattern before and after heat-treatment.

2012 American Chemical Society

Abstract:
Titanium dioxide, or titania, is an inorganic material commonly used as a whitening agent in food and toothpaste. It is also used as one of the main active ingredients in sunscreens. The properties that make titania useful in commercial applications namely its whitening ability and high refractive index are now being exploited in a wide range of technological applications.

Nanomaterials: Formation in a flash - A new lithography technique enables the production of nanoscale patterns of titania for high-tech applications

Singapore | Posted on July 6th, 2012

One particular area of interest has been the application of titania in dye-sensitized solar cells devices that can be used to convert sunlight into electricity. Such application often requires the formation of intricate surface patterns, with the key limiting factors for development being cost and speed of processing. Now, Ramakrishnan Ganesan, Mohammad Saifullah and co-workers at the A*STAR Institute of Materials Research and Engineering have described the use of a technique called step-and-flash imprint lithography (SFIL) to produce such patterns on the nanoscale.

"The precursor method to SFIL is thermal nanoimprint lithography, which is extremely time-consuming as it requires temperature-cycling processes to form a pattern," explains Saifullah. "A mold could be pressed into a heated (and softened) resist material or a liquid precursor could be forced into a mold and then hardened upon heating."

Newer processes eliminate the need for heating by using irradiation with ultraviolet (UV) light to harden the polymer. Although this process may be ideal for organic polymer materials, it is more problematic when using inorganic materials such as titania as the liquid precursor materials are highly viscous and do not spread easily. As a result, the dispensing nozzle may sometimes become blocked.

The chemicals used to make titania can also be unstable in solution, so the team had to identify a mixture of components that offered a combination of stability and low viscosity. "We found that an allyl functionalized titanium complex was stable in combination with other polymer precursors," explains Saifullah. The final component of the mixture is a photoinitiator which starts the polymerization process upon irradiation with UV light.

The mixture was dispensed onto the surface in the form of droplets, and the mold pressed into place to help the liquid spread. Irradiation with UV light results in hardening of the pattern, after which the mold can be removed. A final heating step burns away the organic material, leaving behind a shrunken version of the original pattern made from titania (see image). Significantly, the aspect ratio of the pattern is maintained after the heat-treatment process.

"Our current method is quite specific to titania, but after tackling this most important material, we hope to develop similar procedures for other inorganic materials," says Saifullah.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Materials Research and Engineering

References:

Ganesan, R. et al. Direct patterning of TiO2 using step-and-flash imprint lithography. ACS Nano 6, 1494-1502 (2012). (Direct link to article below)

####

For more information, please click here

Contacts:
A*STAR Research

Copyright © Agency for Science, Technology and Research (A*STAR)

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 Links

Agency for Science, Technology and Research (A*STAR):

Institute of Materials Research and Engineering:

Link to original article in ACS Nano:

Related News Press

News and information

Self-assembling biomaterial forms nanostructure templates for human tissue formation April 27th, 2015

International research team discovers new mechanism behind malaria progression: Findings provide a new avenue for research in malaria treatment April 27th, 2015

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Cacao Seed Extract Used in Production of Catalytic Nanoparticles April 27th, 2015

Chemistry

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

Cacao Seed Extract Used in Production of Catalytic Nanoparticles April 27th, 2015

Discoveries

More is less in novel electronic material: Adding electrons actually shrinks the system April 27th, 2015

Two-dimensional semiconductor comes clean April 27th, 2015

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Announcements

Scientists join forces to reveal the mass and shape of single molecules April 27th, 2015

The 16th Trends in Nanotechnology International Conference (TNT 2015) unveils 25 Keynote Speakers: Call for abstracts open April 27th, 2015

Graphenea celebrates fifth anniversary April 27th, 2015

Sensor Designed in Iran Able to Remove Formaldehyde Gas from Environment April 27th, 2015

Energy

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

'Holey' graphene for energy storage: Charged holes in graphene increase energy storage capacity April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Solar/Photovoltaic

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Printing Silicon on Paper, with Lasers April 21st, 2015

Better battery imaging paves way for renewable energy future April 20th, 2015

The microscopic topography of ink on paper: Researchers have analyzed the varying thickness of printed toner in unprecedented 3-D detail, yielding insights that could lead to higher quality, less expensive and more environmentally-friendly glossy and non-glossy papers April 14th, 2015

Printing/Lithography/Inkjet/Inks

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

New class of 3D-printed aerogels improve energy storage April 22nd, 2015

Printing Silicon on Paper, with Lasers April 21st, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project