The next-generation solar cell is fully recyclable

With the anticipated surge in electricity demand due to the expansion of artificial intelligence and the electrification of transportation, sustainable energy sources must advance to prevent further environmental impact. Solar power has long been considered a viable renewable energy source, with silicon-based panels dominating the market for over three decades. However, as first-generation silicon panels reach the end of their lifespan, waste management poses a major challenge.

"There is currently no effective technology to handle the waste from silicon solar panels. As a result, outdated panels are being discarded in landfills, leading to vast amounts of electronic waste," explained Xun Xiao, postdoctoral researcher at Linkoping University's Department of Physics, Chemistry, and Biology (IFM).

Feng Gao, a professor of optoelectronics at the same department, emphasized the importance of considering recyclability in emerging solar technologies: "If we don't have a recycling solution in place, perhaps we shouldn't introduce new solar cell technologies to the market."

Perovskite solar cells are among the most promising alternatives for next-generation solar technology. These cells are lightweight, flexible, and transparent, making them suitable for various surfaces, including windows. Additionally, they achieve energy conversion efficiencies of up to 25 percent, rivaling silicon-based solar cells.

"Many companies are eager to commercialize perovskite solar cells, but we must ensure that they do not contribute to landfill waste. Our project introduces a method where all components of perovskite solar cells can be reused without sacrificing performance," said Niansheng Xu, postdoctoral researcher at Linkoping University.

Although perovskite solar cells have a shorter lifespan than their silicon counterparts, it is crucial to develop an efficient and environmentally friendly recycling process. Additionally, these cells contain a small amount of lead, essential for high efficiency but requiring proper handling to prevent environmental contamination. In many parts of the world, manufacturers are legally obligated to recycle end-of-life solar cells sustainably.

Existing recycling methods for perovskite solar cells often rely on dimethylformamide, a toxic and potentially carcinogenic solvent commonly found in paint removers. The Linkoping researchers have devised an innovative approach that replaces this hazardous chemical with water, significantly reducing environmental risks. This method enables the recovery of high-quality perovskite materials from the water-based solution.

"We can recover every component-the glass covers, electrodes, perovskite layers, and charge transport layers," Xiao added.

The next phase of research will focus on scaling up this process for industrial applications. In the long term, scientists believe that perovskite solar cells will become a key component of the global energy transition, particularly as supporting infrastructure and supply chains evolve.

Research Report:Aqueous based recycling of perovskite photovoltaics