“Silver nanoparticles are widely used, with more than 500 tons of annual global production and a market size of more than $2 billion per year,” Gupta said, citing biomedical applications such as sensing and imagery.
He added that if his process could be perfected, solar panel manufacturers and recycling companies would have an incentive to take back old panels and get more out of them, to the benefit of consumers and the environment.
The patent-pending technology will be a greener approach than the existing silver mining method, which uses nitric acid to recover silver from old or broken silicon solar cells – “a technique that can be environmentally harmful and inefficient,” said John Horst, a spokesman for the DOE’s Renewable Energy and Energy Efficiency Division.
Solar panels have a useful life of up to 25 years. Manufacturers don’t tend to refurbish panels after that because of the cost. The main route for the reuse of old panels has therefore been through glass recycling facilities, where the glass and sometimes the frames are recovered, before the other elements are burned or otherwise disposed of.
By 2050, solar module waste is expected to reach 78 million tonnes.
“It’s hard to compete with the cheap, environmentally-unfriendly landfill approach,” Gupta said. But he and his team are convinced that the new technology can.
Professor Scott Acton, chair of the Department of Electrical and Computer Engineering, said research at the National Science Foundation’s Industry-University Cooperative Laser Research Center in Gupta promises to be transformative.
“Professor Gupta’s advances in research and innovative use of laser ablation represent a key step in realizing clean, sustainable and inexpensive energy sources for the future,” Acton said.
The Small Innovative Projects in Solar program, part of President Joe Biden’s effort to address the climate crisis through the Department of Energy, focuses on projects that can demonstrate impact within the first year. .
Gupta’s project is part of the university’s Grand Challenge research initiatives focused on environmental resilience and sustainability.