Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanotechnology Helps Scientists Keep Silver Shiny

30.10.2012
There are thousands of silver artifacts in museum collections around the world, and keeping them shiny is a constant challenge. So scientists are using new technology to give conservators a helping hand.

A team of researchers led by Ray Phaneuf, a professor of materials science and engineering at the University of Maryland, College Park, has partnered with The Walters Art Museum in Baltimore to investigate less labor-intensive ways to protect silver artifacts from tarnishing.

The new techniques, which might keep silver surfaces shiny for longer than traditional methods, could help ensure that historically important artifacts are preserved for future generations to learn from and enjoy. The researchers will present their work at the AVS 59th International Symposium and Exhibition, held Oct. 28 – Nov. 2, in Tampa, Fla.

Silver tarnishes when hydrogen sulfide in the air reacts with the silver, forming an unsightly black layer of silver sulfide on the surface of the artifact. If the tarnish appears on Grandma's silver flatware set, a little polisher and some elbow grease will easily remove it. But polishing, which works by dissolving or grinding away the silver-sulfide layer, can also remove some of the underlying silver, an undesirable outcome for priceless works of art.

Currently museum conservators can apply a thin layer of nitrocellulose lacquer to protect the silver. The coating is often hand-painted by a trained specialist and must be removed and reapplied an average of every thirty years. Phaneuf notes that it is difficult to apply a layer of even thickness over an entire piece, and the process of applying, removing, and reapplying the film is time-consuming.

"We did a quick back-of-the envelope calculation and found that for a big museum like the Metropolitan Museum of Art in New York, treating their entire silver collection with nitrocellulose films would likely be a never-ending task," says Phaneuf.

A quicker conservation method is to display silver pieces in an enclosed chamber with filtered air, but the chambers often leak, are expensive to install and maintain, and putting an artifact behind glass may prevent visitors from seeing the object up-close and from multiple angles.

Phaneuf and his colleagues are investigating a technique that could overcome some of the shortcomings of current preservation methods. Called atomic layer deposition (ALD), the process gives scientists atomic-level control over the thickness of a transparent oxide film that they grow on the surface of silver objects. By running a series of surface-limited chemical reactions, researchers can build the protective film one atom-thick layer at a time. The films Phaneuf and his team have tested are under 100 nanometers thick, less than 1/1000th the thickness of a human hair.

Phaneuf and his colleagues are currently experimenting by applying ALD films to highly uniform silver test wafers. The uniformity of the wafers allows the researchers to control variables, such as the composition of the silver, in order to create a model of the tarnishing kinetics as sulfur diffuses through the ALD film.

"This is when we get to put on our physicists' hats," Phaneuf says of simplifying the test cases and building a predictive model. The test case results showed two components to the concentration profile, indicating a faster rate of sulfur diffusion through tiny pinholes in the protective oxide film. The researchers are now experimenting with multilayer films that plug these pinholes.

Before the researchers use ALD on prized museum pieces, they will need to demonstrate that the coating can be removed without damaging the artifact, and that the thin film will have a minimal effect on the aesthetic look of the silver. In terms of appearance, ALD films may have another advantage over conventional nitrocellulose lacquer, which can yellow with age. Phaneuf and his colleagues are performing tests to measure how the thickness of the ALD films affects the way silver reflects light.

"Untreated silver beautifully reflects white light," Phaneuf explains. "You don't want the protective film to create interference effects that make it look blue or yellow." The expert eyes of art conservators will also help the researchers judge their success in this respect.

Phaneuf says that collaborating museums may soon allow the team to test their methods on forgeries of silver artifacts, and by year's end the team should be working with genuine pieces. "There is no shortage of complex objects this method might be applied to," Phaneuf notes. "There is a lot of interest now in the conservation community in how nanotechnology and other high technologies can be used to preserve art."

MORE INFORMATION ABOUT THE AVS 59th INTERNATIONAL SYMPOSIUM & EXHIBITION
The Tampa Convention Center is located along the Riverwalk in the heart of downtown Tampa at 333 S. Franklin St., Tampa, Florida, 33602.
USEFUL LINKS:
Main meeting website:
http://www2.avs.org/symposium/AVS59/pages/greetings.html
Technical Program:
http://www.avssymposium.org/
Housing and Travel Information:
http://www2.avs.org/symposium/AVS59/pages/housing_travel.html
PRESS REGISTRATION
The AVS Pressroom will be located in the Tampa Convention Center. Your complimentary media badge will allow you to utilize the pressroom to write, interview, collect new product releases, review material, or just relax. The media badge will also admit you, free of charge, into the exhibit area, lectures, and technical sessions, as well as the Welcome Mixer on Monday evening and the Awards Ceremony and Reception on Wednesday night. Pressroom hours are Monday-Thursday, 8-5 p.m.
To register, please contact:
Della Miller, AVS
E-mail: della@avs.org
This news release was prepared for AVS by the American Institute of Physics (AIP).
ABOUT AVS
Founded in 1953, AVS is a not-for-profit professional society that promotes communication between academia, government laboratories, and industry for the purpose of sharing research and development findings over a broad range of technologically relevant topics. Its symposia and journals provide an important forum for the dissemination of information in many areas of science and technology, enabling a critical gateway for the rapid insertion of scientific breakthroughs into manufacturing realities.
Della Miller
AVS
Phone: 530-896-0477
Email: della@avs.org
Catherine Meyers
AIP
Phone: 301-209-3088
Email: cmeyers@aip.org

Della Miller | EurekAlert!
Further information:
http://www.avs.org

More articles from Materials Sciences:

nachricht Scientists create innovative new 'green' concrete using graphene
24.04.2018 | University of Exeter

nachricht Neutrons provide insights into increased performance for hybrid perovskite solar cells
24.04.2018 | DOE/Oak Ridge National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Industrial Maturity of Electrically Conductive Adhesives for Silicon Solar Cells Demonstrated

25.04.2018 | Power and Electrical Engineering

Electrode shape improves neurostimulation for small targets

25.04.2018 | Medical Engineering

Silicon as a new storage material for the batteries of the future

25.04.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>