This Next-Generation Perovskite Solar Cell Is Fully Recylcable — Just Add Water
"If we don’t know how to recycle them," co-author Feng Gao suggests of rival designs, "maybe we shouldn't put them on the market at all."
Researchers from Linköping University, Cornell University, the University of Toledo, and Westlake University, have come up with a way to address the issue of what to do when a solar panel reaches the end of its useful life — by creating a next-generation solar cell that can be fully recycled.
"There is currently no efficient technology to deal with the waste of silicon panels," explains first author Xun Xiao of the problem the team set out to solve, in a project which could make the most popular green energy technology even greener. "That's why old solar panels end up in the landfill. Huge mountains of electronic waste that you can't do anything with."
"We need to take recycling into consideration when developing emerging solar cell technologies," adds co-corresponding author Feng Gao. "If we don’t know how to recycle them, maybe we shouldn't put them on the market at all."
The team's solution is a next-generation solar cell design, which uses lightweight and easily-manufactured perovskites — creating a transparent cell that can be installed on windows, in addition to on roofs and other surfaces, with a 25 percent conversion efficiency. It's not the first perovskite-based cell around, by any means, but it is claimed to be the first which addresses the biggest problem with the material: a relatively short operation life.
Where rival designs rely on a hazardous solvent called dimethylformamide to dismantle and recycle at the end of their life, the team's approach results in a cell in which the degraded perovskites can be dissolved in water — and high-quality perovskites recovered from the resulting solution for use in more solar cells. "We can recycle everything," Xiao claims, "covering glasses, electrodes, perovskite layers, and also the charge transport layer."
"There are many companies that want to get perovskite solar cells on the market right now," notes co-author Niansheng Xu, "but we’d like to avoid another landfill. In this project, we've developed a method where all parts can be reused in a new perovskite solar cell without compromising performance in the new one."
The team's work has been published under open-access terms in the journal Nature; the next step, the researchers say, is to work on scaling the approach for use in industrial-scale production.
Main article image courtesy of Thor Balkhed/Linköping University.