New surface treatment takes solar panels beyond 33% efficiency

Researchers have achieved a significant breakthrough in perovskite silicon tandem solar cells, surpassing the long-standing efficiency limit of silicon-based panels. While traditional silicon solar cells convert just under 30% of sunlight into electricity, the new approach combines a perovskite top layer with a textured silicon bottom layer, enabling the capture of a broader spectrum of sunlight. The key advancement lies in successfully applying surface passivation—a technique that reduces energy-wasting defects—on textured silicon surfaces commonly used in mass production. By depositing 1,3-diaminopropane dihydroiodide on the uneven perovskite surface, the team attained a conversion efficiency of 33.1% and an open-circuit voltage of 2.01 volts, marking a crucial step toward scalable, highly efficient solar panels. The study also uncovered that passivation behaves differently in perovskite compared to silicon: whereas in silicon it affects only the surface, in perovskite it influences the entire