Channeling Ions Into Defined Paths Improves Perovskite Solar Cells Stability - Universities Research

• Researchers from North Carolina State University, Pennsylvania State University and University of North Carolina at Chapel Hill have found that channeling ions into defined pathways in perovskite materials improves the stability and operational performance of perovskite solar cells. This breakthrough in sustainable energy news could revolutionize photovoltaic technology.

What happened? 

Researchers from North Carolina State University, Pennsylvania State University and University of North Carolina at Chapel Hill have found that channeling ions into defined pathways in perovskite materials improves the stability and operational performance of perovskite solar cells. The team's recent study presented a multiscale diffusion framework that describes vacancy-mediated halide diffusion in polycrystalline metal halide perovskites, differentiating fast grain boundary diffusivity from volume diffusivity that is two to four orders of magnitude slower. This breakthrough, published in Nature Materials, could revolutionize photovoltaic technology. 

Why does it matter?

Perovskite materials have -- to date -- not been able to sustain long term operational stability in perovskite solar cells due to migrating ions. When a voltage is applied to a perovskite, it causes ions to migrate through the material, leading to chemical and structural changes in the material that ultimately make the materials inefficient and unstable. The research team showed that grains are better protected from impairment when the ions move predominantly along the grain boundary, leading to the conclusion that designing stronger grain boundaries that protect the grains is essential to block migrating ions and other harmful species like oxygen from entering the grains. 

What's next?

This research could also inform the development of more efficient energy storage technologies. The work has advanced our fundamental understanding of how ions move through any crystalline material that can carry charge, not just halide perovskites. Researchers are now looking into how this knowledge may inform the engineering of faster ion conductors for energy storage applications.  This research could be a major step towards the development of more sustainable and efficient energy sources.