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Glenn Gates, Walters Art Museum, DMR 1041803

Outcome: Material scientists at the University of Maryland are collaborating with art conservators at the Walters Art Museum to optimize a mineral-based coating to reduce silver corrosion or tarnish and preserve silver artworks.

Impact: The coating developed by the research team will preserve silver artwork and reduce the costs to maintain silver art collections in museums worldwide.

Explanation: Silver artwork in museums is traditionally protected from tarnish or corrosion using a solvent-based barrier coating called lacquer. However, lacquers only last about 20-30 years before they must be removed and painstakingly reapplied. Alternatively, art conservators collaborating with materials scientists have developed a novel mineral-based barrier coating that lasts far more than 100 years protecting silver. Using a technique from nanotechnology called “atomic layer deposition” or ALD, an alumina (Al2O3) barrier coating is created on silver. Researchers are now examining if the ALD-alumina coating can be stripped and reapplied without damaging the underlying silver artwork.

lacqueredsilver

uncoated silver

aluminacoatedsilver

After exposure to tarnishing H2S vapors for 400 hours, the alumina coating continues to protect the silver, but the conventional lacquered silver coating has failed dramatically