A salt called guanidinium thiocyanate can improve the efficiency and stability of perovskite solar cells, a new class of semiconductor that could make solar power cheaper and more powerful, according to researchers at UCL.
In a study published in the Journal of the American Chemical Society, the team showed that guanidinium thiocyanate can slow and control the way perovskite crystals form during fabrication, creating smoother and more uniform layers. This helps reduce the tiny flaws in the material that can hinder performance and shorten a cell's lifespan.
Tandem perovskite cells - that is, two or more layers of solar cells stacked on top of each other - are seen as the future of ultra-efficient solar energy technology. That is because each layer can be tuned to absorb different parts of the solar spectrum, meaning they can convert more of that light into electricity. The new study used mixed tin-lead perovskites - typically the bottom layer of stacked cells.
