Home / Knowledge / News / Textiles / Thin films of silk produce & combine with metallic particles

Thin films of silk produce & combine with metallic particles

25
Aug '09
Using thin films of silk as templates, researchers have incorporated inorganic nanoparticles that join with the silk to form strong and flexible composite structures that have unusual optical and mechanical properties. This bio-enabled, surface-mediated approach mimics the growth and assembly processes of natural materials, taking advantage of the ability of biomolecules to chemically reduce metal ions to produce nanoparticles—without harsh processing conditions.

Less than 100 nanometers thick, silk-silver nanoparticle composite films formed in this process can be used as flexible mirrors. The technique could also be used to create films that reflect light in specific wavelengths, anti-microbial coatings, thin film sensors, self-cleaning coatings, catalytic materials and potentially even flexible photovoltaic cells.

“We are taking advantage of biological molecules that have the ability to bind metallic ions of silver or gold from solution,” said Vladimir Tsukruk, a professor in the Georgia Tech School of Materials Science and Engineering. “These molecules can create mono-dispersed metallic nanoparticles of consistent sizes under ambient conditions—at room temperature and in a water-based environment without high vacuum or high temperatures.”

Sponsored by the Air Force Office of Scientific Research and the Air Force Research Laboratory, the research was described August 19 at the Fall 2009 National Meeting of the American Chemical Society.

The nanoparticles produced range in size from four to six nanometers in diameter, surrounded by a biological shell of between one and two nanometers. The silk template permits good control of the nanoparticle placement, creating a composite with equally dispersed particles that remain separate. The optical properties of the resulting film depend on the nanoparticle material and size.

“This system provides very precise control over nanoparticle sizes,” said Eugenia Kharlampieva, a postdoctoral researcher in Tsukruk's laboratory. “We produce well-defined materials without the problem of precipitation, aggregation or formation of large crystals. Since the silk fibroin is mono-dispersed, we can create uniform domains within the template.”

Atomic force microscope image shows a silk film on which gold nanoparticles were grown.

Fabrication of the nanocomposites begins by dissolving silk cocoons and making the resulting fibroin water soluble. The silk is then placed onto a silicon substrate using a spin-coating technique that produces multiple layers of thin film that is then patterned into a template using a nanolithography technique.

“Because silk is a protein, we can control the properties of the surface and design different kinds of surfaces,” explained Kharlampieva. “This surface-mediated approach is flexible at producing different shapes. We can apply the method to coat any surface we want, including objects of complex shapes.”

Next, the silk template is placed in a solution containing ions of gold, silver, or other metal. Over a period of time ranging from hours to days, nanoparticles form within the template. The relatively long growth process, which operates at room temperature and neutral pH in a water-based environment, allows precise control of the particle size and spacing, Tsukruk notes.


Must ReadView All

Vietnamese side of the border crossing with Hekou, China. Pic:  Klodien | Dreamstime.com

Textiles | On 27th Nov 2021

Efforts on to boost trade between Chinese & Vietnamese provinces

Trade agencies of Lao Cai province in the northwest region of Vietnam ...

Pic: Shaja | Dreamstime.com

Textiles | On 27th Nov 2021

US’ imports of polyester textured yarn to drop in coming months

The US’ imports of polyester textured yarn of HS code 540233 are...

Pic: Tatiyana Akimova | Dreamstime.com

Textiles | On 27th Nov 2021

Sri Lanka’s textile & garment exports on path to cross $5bn this year

After registering a steep fall of 21 per cent year-on-year to $4.423...

Interviews View All

Textile Industry, Head honchos

Textile Industry
Head honchos

Marry craft and utility

Textile Industry, Head honchos

Textile Industry
Head honchos

Delay in adopting water sustainability both financially & environmentally...

Textile Industry, Head honchos

Textile Industry
Head honchos

Extension of RoSCTL to boost textile exports

Erwin Devloo,

Erwin Devloo

The Picanol Group is a diversified industrial group active worldwide in...

Shyam Gupta,

Shyam Gupta

Established by <b>Shyam Gupta</b> in 1978, Gargee Designer's (GD) offers...

Shambhu Nath Jha,

Shambhu Nath Jha

Leading research and consulting firm Fact.MR recently launched a report on ...

Madison Maxey, Loomia

Madison Maxey
Loomia

Loomia designs and manufactures soft circuit systems that can be produced...

Daniel Odermatt, Ventile

Daniel Odermatt
Ventile

Ventile is a registered trademark used to brand a special high-quality...

Karan Bose, Hula Global

Karan Bose
Hula Global

Hula Global, a leading isolation gown manufacturer in India, has been...

Suman Nathwani, Suman Nathwani

Suman Nathwani
Suman Nathwani

Designer <b>Suman Nathwani</b> talks about her journey of opening a...

Manish Malhotra, Label Manish Malhotra

Manish Malhotra
Label Manish Malhotra

A multitalented designer and founder of an eponymous label, Manish...

Vidur Adlakha & Riccardo Bennidini, La Fuori

Vidur Adlakha & Riccardo Bennidini
La Fuori

With an active presence in US, Italy and India, clothing brand La Fuori...

Press Release

Press Release

Letter to Editor

Letter to Editor

RSS Feed

RSS Feed

Submit your press release on


editorial@fibre2fashion.com

Letter To Editor






(Max. 8000 char.)

Search Companies





SEARCH

Leave your Comments


November 2021

Subscribe today and get the latest update on Textiles, Fashion, Apparel and so on.


Advanced Search