Plant-virus proteins guide gold nanoparticles into eco-friendly sheets for solar tech

Using proteins from a common tobacco plant virus, McGill chemistry researchers have developed a simple, eco-friendly way to arrange gold nanoparticles into ultrathin sheets, strengthening the particles' optical properties.

The result: cheaper, safer materials for solar panels, sensors and advanced optical devices.

Gold nanoparticles are only effective in strengthening optical signals when the nanoparticles are arranged on a surface and spaced at exact distances.

Until now, creating those patterns required harsh chemicals and tightly controlled lab conditions. The McGill team's breakthrough was to modify a tobacco mosaic virus so that it would self-assemble into sheets in water at room temperature, with the nanoparticles properly spaced.

"If you just chuck these nanoparticles on a surface, some fraction of them will randomly cause enhancement," said Associate Professor and co-author Amy Blum. "But if you can get them to be at a fixed good distance, then the whole surface is active." The result is a nanomaterial that can be made at a lower cost and with less environmental impact, compared to the existing method.

Image source: Amy Blum.