Researchers advance perovskite-silicon tandem solar cell production

Researchers in Germany have made advancements in the production of perovskite-silicon tandem solar cells, which offer higher efficiency than standard silicon cells by absorbing different parts of the solar spectrum.

Scientists from the University of Freiburg have developed a new process chain that produces the perovskite layer entirely without solvents. By utilizing a vacuum process involving sequential evaporation, the team successfully transitioned materials into a gas phase to deposit them onto silicon substrates, avoiding the complexities of solubility and layer homogeneity often associated with solution-based methods.

Complementary research at the Helmholtz-Zentrum Berlin (HZB) addressed challenges regarding layer uniformity on textured silicon surfaces. Using BESSY II facilities, researchers identified that self-assembled monolayers (SAMs) and co-evaporated perovskite layers often form unevenly on industrial-grade silicon. To resolve this and prevent the formation of unwanted lead iodide at the interface, the team implemented a cesium chloride (CsCl) seeding layer to ensure more uniform growth.